Channel code assignment according to gain factor

ABSTRACT

It is an object to propose a way to assign channelization that is applicable to a case in which the number of multiplexing of DPDCHs (Dedicated Physical Data Channels) is at least five for overshoot of HPSK (Hybrid Phase Shift Keying) modulation. Assignment of channelization codes is set as follows. For all possible combinations of channelization assigned to given data channels and control channels, a transition θ 1  from the first chip to the second chip and a transition θ 2  from the third chip to the fourth chip are obtained. For each transition, 0 degrees or 180 degrees is desirable, and 90 degrees is the worst, so that a combination is obtained in which squares of sine of respective transitions become the smallest. Consequently, by obtaining a combination that makes sin 2  θ 1 +sin 2  θ 2  the smallest, the one that is close to the most desirable combination can be obtained.

TECHNICAL FIELD

The present invention relates to, for example, CDMA (Code DivisionMultiple Access) and to assignment of Walsh codes. In particular, itrelates to a way to assign channelization codes in the UplinkEnhancement.

BACKGROUND ART

With CDMA, a signal transmission is performed by spreading an inputsignal using channelization codes and scrambling codes. This ratio ofbandwidths of a transmission signal and an input signal is called aspreading factor (SF) in CDMA. The channelization code is used fordistinguishing a channel; the scrambling code is used for distinguishinga user.

In drawings explained below, the same numeral signs (for example, 100)are used for the same parts or corresponding parts. To differentiateeach of the same parts or the corresponding parts, a sign consisting ofa numeral sign and an alphabetical sign (for example, 100 a, 100 b) isused. FIG. 29 shows an explanatory drawing of a multiplexingtransmission of uplink data channels when a communication apparatusdescribed in 3GPP (3^(rd) Generation Partnership Project) transmits datato a base station. At least one DPDCH (Dedicated Physical Data Channel),one DPCCH (Dedicated Physical Control Channel), a high-speed controlchannel for HS-DSCH (Dedicated Physical Control Channel for HS-DSCH(High Speed Downlink Shared Channel): HS-DPCCH) are multiplexed andtransmission is carried out.

A communication apparatus of FIG. 29 shows a detailed configuration of amodulating unit 902 illustrated in FIG. 1, which processes IQmultiplexing of plural data channels and control channels of an I sideand a Q side to generate a complex signal. FIG. 29 includes multipliers100 a through 100 c at the I side and 100 e through 100 g at the Q sidewhich multiply spread codes (channelization codes) C_(d,1) throughC_(d,6) for separating channels to data of DPDCH1 through DPDCH6 whichare data channels, a multiplier 100 h at the Q side which multiplies aspread code C_(c) for separating channels to control data of the controlchannel DPCCH, a multiplier 100 d at the I side and a multiplier 100 iat the Q side which multiply a spread code C_(hs) for separatingchannels to control data of a newly added control channel HS-DPCCH.Further, multipliers 101 a through 101 c at the I side and 101 e through101 g at the Q side which multiply an amplitude factor β d for DPDCHs tooutput signals from the multipliers 100 a through 100 c at the I sideand multipliers 100 e through 100 g at the Q side are provided; amultiplier 101 h which multiplies an amplitude factor β c for a DPCCH tooutput signals from the multiplier 100 h at the Q side is provided; andmultipliers 101 d and 101 i which multiplies an amplitude factor β hsfor an HS-DPCCH to output signals from the multiplier 100 d at the Iside and the multiplier 100 i at the Q side are provided. Yet further,an adder 102 a for adding outputs signals from the multipliers 101 athrough 101 d at the I side, an adder 102 b for adding output signalsfrom the multipliers 101 e through 101 i at the Q side, a multiplier 103for multiplying an imaginary number j to an output signal from the adder102 b at the Q side, an adder 104 for carrying out a complex addition ofoutputs from the adder 102 a at the I side and the multiplier 103 at theQ side, and a multiplier 105 for multiplying a scrambling codeS_(dpch,n) to an output signal from the adder 104 are included.

Next, an operation will be explained. To each channel, the multiplier100 multiplies a channelization code C_(SF,k). Here, SF shows aspreading factor, and k shows a code number. It is assumed that N is amultiplexing number. To multiplex DPDCHs having the multiplexing numberN(N≧2), channelization codes are determined for each channel as follows:The channelization code for a DPCCH is C_(256,0). The channelizationcodes for an HS-DPCCH are C_(256,1) (N=2, 4, 6) and C_(256,32) (N=3, 5).The channelization code for DPDCH_(x) (DPDCH_(x): x is a channel number)is C_(4,1) (x=1, 2), C_(4,3) (x=3, 4), and C_(4,2) (x=5, 6). Next, themultiplier 101 carries out weighing. β shows a weighing function, whichis a gain factor whose weight varies according to a kind of channel.These are added by an accumulator (an adder 102). Then, the multiplier103 and an adder 104 are used to make a transmission signal a complexnumber. Finally, the multiplier 105 multiplies it by a scrambling codeS_(dpch,n) to carry out transmission.

Transmission is carried out using HPSK (Hybrid Phase Shift Keying)modulation in 3GPP. In HPSK modulation, a signal output from aconfiguration shown in FIG. 30 is used as the scrambling code. W₀ and W₁have repeated patterns of W₀=[1,1] and W₁=[1,−1], respectively, and arereferred to as Walsh Rotators. C_(long,1,n) and C_(long,2,n) are GoldSequences having different phases, respectively. First, a decimatingunit 200 decimates an even-numbered chip of C_(long,2,n), and anodd-numbered chip that is located directly before is inserted instead ofthe decimated chip. Next, the multiplier 201 multiplies a signal outputfrom the decimating unit 200 and W₁. Then, it is made to be a complexnumber by the multiplier 202 and the adder 203. Finally, C_(long,1,n) ismultiplied by the multiplier 204. At this time, as a complex signalinput to the multiplier 204, a complex number is input to aneven-numbered chip which is conjugate with an odd-numbered chip. Bymultiplying an output scrambling code S_(dpch,n) to this signal, a phasevariation from an odd-numbered chip to an even-numbered chip alwaysbecomes 90 degrees when the signal input to the multiplier 105, that is,multiplexed signal, has the same phase continuously.

FIG. 31 shows a tracking of the transmitted chip on a complex plane. Aphase of the chip in this explanation means a phase of a point on thecomplex plane as shown in FIG. 31, and a phase variation means avariation of phase angles during a transition among the chips. As shownin the figure, when the phase variation is 0 degrees or 180 degrees, apeak value of an amplitude becomes large because of overshoot, whichaffects an amplifier badly. Further, it is understood that when thephase variation is 90 degrees, the peak does not increase and the phasevariation is ideal. Accordingly, when it is considered that the phaserotates by 90 degrees by the scrambling code, the phase variation froman odd-numbered chip to an even-numbered chip is desired to be 0 degreesor 180 degrees at a stage of multiplexing the data channels beforeapplying the scrambling code. A method to resolve the overshoot usingonly the channelization code C_(SF,k) of which 0≦k≦SF/2−1 or only thechannelization code C_(SF,k) of which (SF/2) ≦k≦(SF−1) is disclosed inJP2002-33716 as a code assignment method in consideration of the phasevariation from an odd-numbered chip to an even-numbered chip.

JP2002-33716 (Patent document 1) notices that SF is 4 and selects acombination so that the phase variations both from the first chip to thesecond chip and from the third chip to the fourth chip should be 0degrees or 180 degrees when one piece of data is spread. Further, thispatent document 1 assumes that, by using that the gain factor of a DPCCHis very small, the DPCCH does not affect the phase variation. FIG. 32shows a case of using only the channelization code C_(4,k) of which0≦k≦1 when the number of multiplexed DPDCHs is three. FIG. 33 shows acase of using only the channelization code C_(4,k) of which 2≦k≦3 whenthe number of multiplexed DPDCHs is three, and FIG. 34 shows a case inwhich the number of multiplexed DPDCHs is four. When C_(4,2) is assignedto DPDCH₁, C_(4,2) is assigned to DPDCH₂, and C_(4,3) is assigned toDPDCH₃ as shown in FIG. 33, chips output from the IQ become as follows:I=(2, −2, 0, 0)Q=(1, −1, 1, −1)

Here, the phase variation from the first chip to the second chip is 180degrees, and the phase variation from the third chip to the fourth chipis also 180 degrees. Accordingly, this assignment of the channelizationcodes is ideal.

This method, however, can use only one of combinations of thechannelization C_(4,0) and C_(4,1), or the channelization codes C_(4,2)and C_(4,3), so that this method cannot be applied to a case in whichthe number of multiplexed DPDCHs is at least five. Further, only one ofthe combinations of C_(4,0) and C_(4,1) and C_(4,2) and C_(4,3) can beused, only a case when the phase variation is 0 degrees or 180 degreesis considered. Accordingly, when the phase variation does not become 0degrees or 180 degrees, it is not considered how much the phasevariation should be set. Further, since only a DPCCH and a DPDCH areconsidered, there is a problem that the method cannot be applied to acase including another channel such as an HS-DPCCH. For example, it isassumed that an HS-DPCCH having the gain whose magnitude is the same asa DPDCH is added to the example of FIG. 33. In case of the number ofmultiplexing N=3, since the channelization code for the HS-DPCCH isC_(256,32), (1, 1, 1, 1) or (−1, −1, −1, −1) is input, when it isconsidered by 4-chip unit. For example, in case of (1, 1, 1, 1), chipsoutput from the IQ become:I=(2, −2, 0, 0)Q=(1, −1, 1, −1)+(1, 1, 1, 1)=(2, 0, 2, 0)The phase variation from the first chip to the second chip is 135degrees and the phase variation from the third chip to the fourth chipis not known, since it passes the point of origin. As a result, itcannot be said that the channelization codes are assigned optimally.

In the next specification, Release 6 (Rel-6), introduction of uplinkenhancement is considered. In the uplink enhancement, other than theconventional transport channel DCH (Dedicated Channel), E-DCH (EnhancedDedicated Channel) is also superimposed on a DPDCH. Further, it has beenconsidered to introduce an E-DPCCH (Enhanced DPCCH). FIGS. 35 and 36show examples of multiplexing transmission of uplink data channels inthe uplink enhancement. A broken line in the figure shows that thetransmission may not exist depending on the number of multiplexedchannels. In FIG. 35, DPDCHs superimpose DCH or E-DCH, and an E-DPCCH istreated as one control channel. Further, only for DPDCH₁ it isdetermined that DCH is superimposed on it. Further, in FIG. 36,multiplexing is done so that DCH, E-DCH, and E-DPCCH are superimposedonly on DPDCH₁, and DCH and E-DCH are superimposed on other DPDCHs.Besides, various ways of multiplexing are proposed. Here, since the dataamount of a DPDCH that superimposes E-DCH or an E-DPCCH is large, theirgain factor becomes larger than that of a DPDCH that superimposes onlyDCH.

-   Patent Document 1: JP2002-33716-   Non-patent Document 1: 3GPP Technical Report TR25.896 v1.2.1

DISCLOSURE OF THE INVENTION

Problems to be Solved by the Invention

The conventional assignment of channelization codes for a data channelhas a problem that PAR (Peak to Average Ratio) is increased because ofovershoot due to HPSK (Hybrid Phase Shift Keying) modulation. As amethod to resolve this, JP2002-33716 discloses a method in which a phasevariation from the first chip to the second chip and a phase variationfrom the third chip to the fourth chip are observed, and codes areassigned so that these phase variations should be 0 degrees or 180degrees that is an ideal phase variation in HPSK modulation. However,when the number of multiplexing is at least five for DPDCHs, there is nochannelization code to be assigned, so that the method cannot be appliedto such a case. Further, only a case is considered when the phasevariation is 0 degrees or 180 degrees. Therefore, it is not consideredhow much the phase variation should be when the phase variation does notbecome 0 degrees or 180 degrees. Further, there is a problem that only acase with two kinds of channels of a DPDCH and a DPCCH are considered,so that the method cannot be applied to a case including other channels,for example, an HS-DPCCH.

The present invention aims to propose a way to assign channelizationcodes when the number of multiplexed data channels is plural and thegain factors are different.

In particular, in uplink enhancement, it is an object to propose a wayto assign the channelization codes to the data channels having differentgain factors.

Further, the present invention aims to propose a way to assign thechannelization codes that is adaptive to HSDPA (High Speed DownlinkPacket Access).

Yet further, it is an object to propose a way to assign thechannelization codes, which is effective to cases that an HS-DPCCH is atthe I side, at the Q side, alternatively at I and Q sides depending onthe number of multiplexed data channels, or there is no HS-DPCCH.

Further, it is an object to propose an effective way of assignment, inparticular, when the number of multiplexed data channels is at leastfive.

Further, it is an object to propose a way which is adaptive to bothcases when assignment of the channelization codes is determined based onthe number of multiplexing and performance of the data channels andmaintained to the end and when assignment of the channelization codes isdetermined for each frame.

Means to Solve the Problems

A communication apparatus according to the present invention has acontrolling unit for controlling assignment of channelization codes, and

the controlling unit includes:

a code combination creating unit for creating a plurality ofcombinations of the channelization codes;

an inter-chip phase variation calculating unit for calculating eachphase variation among a plurality of chips for each combination of thechannelization codes created by the code combination creating unit;

a code combination determining unit for obtaining by calculation acombination of channelization codes of which a sum of overshootgenerated by each phase variation among a plurality of chips calculatedby the inter-chip phase variation calculating unit is small, anddetermining an obtained combination as a combination of codes to beused; and

a code assignment instructing unit for instructing assignment of thechannelization codes based on the combination of codes determined by thecode combination determining unit.

The inter-chip phase variation calculating unit obtains a phasevariation between a first chip and a second chip and a phase variationbetween a third chip and a fourth chip, and

the code combination determining unit determines a combination ofchannelization codes of which the phase variation between the first chipand the second chip and the phase variation between the third chip andthe fourth chip are respectively close to 0 degrees or 180 degrees asthe combination of codes to be used.

The inter-chip phase variation calculating unit obtains a phasevariation α between a first chip and a second chip of an I channel and aQ channel and a phase variation β between a third chip and a fourth chipof the I channel and the Q channel; and

the code combination determining unit determines a combination ofchannelization codes of which a sum of a square of sin(α) and a squareof sin(β) is smallest as the combination of codes to be used.

A communication apparatus according to the present invention includes:

an IQ multiplexing unit for multiplexing a plurality of data channelsand a control channel at an I side and a Q side to generate a complexsignal;

a transmitting unit for modulating and transmitting the complex signalgenerated by the IQ multiplexing unit; and

a controlling unit for controlling assignment of channelization codesfor a data channel and a control channel at the I side and the Q sidemultiplexed by the IQ multiplexing unit; and

the controlling unit includes:

a code assigning unit by factor for, based on a size of a factor that ismultiplied to the data channel and the control channel by the IQmultiplexing unit, assigning a first channelization code to a datachannel of which the factor is large; and

a remaining code assigning unit for assigning a second channelizationcode being different from the first channelization code to a datachannel to which no channelization code has been assigned by the codeassigning unit by factor.

The code assigning unit by factor includes a prohibited code judgingunit for, when a second control channel is added as a control channel,judging which of the I side or the Q side of the IQ multiplexing unitthe second control channel is added, and, at the I side or the Q side towhich the second control channel is added, prohibiting assignment of achannelization code that has a correlation with a channelization code tobe assigned to the second control channel.

The factor is a gain factor; and

the controlling unit, when a number of data channels multiplexed by theIQ multiplexing unit is five, among three data channels at the I side ofthe IQ multiplexing unit, assigns C_(4,2) and C_(4,3) respectively aschannelization codes to two data channels having largest gain factorsand assigns either C_(4,1) or C_(4,0) to a remaining one data channel.

The factor is a gain factor; and

the controlling unit, when a number of data channels multiplexed by theIQ multiplexing unit is six, among three data channels at the I side ofthe IQ multiplexing unit, assigns C_(4,2) and C_(4,3) respectively aschannelization codes to two data channels having largest gain factorsand assigns C_(4,1) to a remaining one data channel, and among threedata channels at the Q side of the IQ multiplexing unit, assigns C_(4,2)and C_(4,3) respectively as channelization codes to two data channelshaving largest gain factors and assigns either C_(4,1) or C_(4,0) to aremaining one data channel.

The controlling unit controls assignment of channelization code C_(SF,k)of which a spreading factor is SF and a code number is k, assigns achannelization code of which the code number k is 0≦k≦(SF/2−1) as thefirst channelization code, and assigns a channelization code of whichthe code number k is (SF/2)≦k≦(SF−1) as the second channelization code.

The controlling unit controls assignment of channelization code C_(SF,k)of which a spreading factor is SF and a code number is k, assigns achannelization code of which the code number k is 0≦k≦(SF/2−1) as thesecond channelization code, and assigns a channelization code of whichthe code number k is (SF/2)≦k≦(SF−1) as the first channelization code.

The controlling unit, in case of assigning channelization codes to adata channel of which the spreading factor SF is 2 and to a data channelof which the spreading factor SF is 4, assigns C_(2,0) to the datachannel of which the spreading factor SF is 2 as the firstchannelization code and assigns C_(4,2) or C_(4,3) to the data channelof which the spreading factor SF is 4 as the second channelization code.

The controlling unit, in case of assigning channelization codes to adata channel of which the spreading factor SF is 2 and to a data channelof which the spreading factor is 4, assigns C_(2,1) to the data channelof which the spreading factor SF is 2 as the first channelization codeand assigns C_(4,0) or C_(4,1) to the data channel of which thespreading factor SF is 4 as the second channelization code.

A communication apparatus according to the present invention includes:

an IQ multiplexing unit for multiplexing a plurality of data channelsand a control channel at an I side and a Q side to generate a complexsignal;

a transmitting unit for modulating and transmitting the complex signalgenerated by the IQ multiplexing unit; and

a controlling unit for controlling assignment of channelization codesfor a data channel and a control channel at the I side and the Q sidemultiplexed by the IQ multiplexing unit; and

the controlling unit includes:

a code assigning unit by data amount for, out of data channelsmultiplexed by the IQ multiplexing unit, judging a data channel of whichdata amount is large, and assigning a first channelization code to thedata channel of which data amount is large; and

a remaining code assigning unit for assigning a second channelizationcode being different from the first channelization code to a datachannel to which no channelization code has been assigned by the codeassigning unit by data amount.

The code assigning unit by data amount includes a prohibited codejudging unit for, when a second control channel is added as a controlchannel, judging which of the I side or the Q side of the IQmultiplexing unit the second control channel is added, and, at the Iside or the Q side to which the second control channel is added,prohibiting assignment of a channelization code that has a correlationwith a channelization code which is to be assigned to the second controlchannel.

The code assigning unit by data amount, out of the plurality of datachannels at the I side and the Q side of the IQ multiplexing unit,judges a data channel of which a number of multiplexing is large as thedata channel of which data amount is large rather than a data channel ofwhich a number of multiplexing is small.

The controlling unit, when a number of data channels multiplexed by theIQ multiplexing unit is five, among three data channels at the I side ofthe IQ multiplexing unit, assigns C_(4,2) and C_(4,3) respectively aschannelization codes to two data channels having largest data amount,and assigns either C_(4,1) or C_(4,0) to a remaining one data channel,and assigns C_(4,2) and C_(4,3) respectively as channelization codes totwo data channels at the Q side of the IQ multiplexing unit.

The controlling unit, when a number of data channels multiplexed by theIQ multiplexing unit is six, among three data channels at the I side ofthe IQ multiplexing unit, assigns C_(4,2) and C_(4,3) respectively aschannelization codes to two data channels having largest data amount,and assigns either C_(4,1) or C_(4,0) to a remaining one data channel,and among three data channels at the Q side of the IQ multiplexing unit,assigns C_(4,2) and C_(4,3) respectively as channelization codes to twodata channels having largest data amount and assigns C_(4,1) to aremaining one data channel.

EFFECT OF THE INVENTION

The present invention enables to automatically determine by calculationa combination of channelization codes with which the overshoot is small.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a configuration of a CDMA terminal according to the firstembodiment.

FIG. 2 shows a configuration of a CDMA base station.

FIG. 3 shows a configuration of a CDMA controlling unit according to thefirst embodiment.

FIG. 4 is an explanatory drawing of data channel multiplex transmissionfor determining assignment of channelization codes by calculating gainfactors when an HS-DPCCH is set as specified in a specificationaccording to the first embodiment.

FIG. 5 is an explanatory drawing of data channel multiplex transmissionfor determining assignment of channelization codes by calculating gainfactors when an HS-DPCCH is fixed to a Q side according to the firstembodiment.

FIG. 6 is an explanatory drawing of data channel multiplex transmissionfor determining assignment of channelization codes by calculating gainfactors when an HS-DPCCH is fixed to an I side according to the firstembodiment.

FIG. 7 shows a flowchart for determining assignment of channelizationcodes by calculating gain factors according to the first embodiment.

FIG. 8 is an explanatory drawing of data channel multiplex transmissionfor determining assignment of channelization codes based on magnitudesof gain factors when there is no HS-DPCCH according to a secondembodiment.

FIG. 9 shows a configuration of a CDMA controlling unit according to thesecond embodiment.

FIG. 10 shows a flowchart for determining assignment of channelizationcodes based on magnitudes of gain factors when there is no HS-DPCCHaccording to the second embodiment.

FIG. 11 shows a configuration of a CDMA controlling unit according to athird embodiment.

FIG. 12 shows an example of assigning channelization codes based on dataamount in case of the number of multiplexing N=2 when there is noHS-DPCCH according to the third embodiment.

FIG. 13 shows an example of assigning channelization codes based on dataamount in case of the number of multiplexing N=3 when there is noHS-DPCCH according to the third embodiment.

FIG. 14 shows an example of assigning channelization codes based on dataamount in case of the number of multiplexing N=4 when there is noHS-DPCCH according to the third embodiment.

FIG. 15 shows an example of assigning channelization codes based on dataamount in case of the number of multiplexing N=5 when there is noHS-DPCCH according to the third embodiment.

FIG. 16 shows an example of assigning channelization codes based on dataamount in case of the number of multiplexing N=6 when there is noHS-DPCCH according to the third embodiment.

FIG. 17 is an explanatory drawing of data channel multiplex transmissionfor determining assignment of channelization codes based on magnitudesof gain factors when an HS-DPCCH is set as specified in a specificationaccording to a fourth embodiment.

FIG. 18 is an explanatory drawing of data channel multiplex transmissionfor determining assignment of channelization codes based on magnitudesof gain factors when an HS-DPCCH is fixed to a Q side according to thefourth embodiment.

FIG. 19 is an explanatory drawing of data channel multiplex transmissionfor determining assignment of channelization codes based on magnitudesof gain factors when an HS-DPCCH is fixed to an I side according to thefourth embodiment.

FIG. 20 shows a configuration of a CDMA controlling unit according tothe fourth embodiment.

FIG. 21 shows a flowchart for determining assignment of channelizationcodes based on magnitudes of gain factors when there is an HS-DPCCHaccording to the fourth embodiment.

FIG. 22 shows a flowchart for determining assignment of channelizationcodes based on magnitudes of gain factors when there is an HS-DPCCHaccording to the fourth embodiment.

FIG. 23 shows a configuration of a CDMA controlling unit according to afifth embodiment.

FIG. 24 shows an example of assigning channelization codes based on dataamount in case of the number of multiplexing N=2 when there is anHS-DPCCH according to the fifth embodiment.

FIG. 25 shows an example of assigning channelization codes based on dataamount in case of the number of multiplexing N=3 when there is anHS-DPCCH according to the fifth embodiment.

FIG. 26 shows an example of assigning channelization codes based on dataamount in case of the number of multiplexing N=4 when there is anHS-DPCCH according to the fifth embodiment.

FIG. 27 shows an example of assigning channelization codes based on dataamount in case of the number of multiplexing N=5 when there is anHS-DPCCH according to the fifth embodiment.

FIG. 28 shows an example of assigning channelization codes based on dataamount in case of the number of multiplexing N=6 when there is anHS-DPCCH according to the fifth embodiment.

FIG. 29 shows a configuration of data channel multiplex transmissiondescribed in 3GPP.

FIG. 30 shows a configuration for creating a scrambling code in HPSKmodulation.

FIG. 31 is a diagram showing a phase variation of a chip on a complexplane.

FIG. 32 shows an example of assignment using only a channelization codeC4,2 or C4,1 when the number N of multiplexing of DPDCHs is 3 accordingto a conventional method.

FIG. 33 shows an example of assignment using only a channelization codeC4,2 or C4,3 when the number N of multiplexing of DPDCHs is 3 accordingto a conventional method.

FIG. 34 shows an example of assignment of channelization codes when thenumber N of multiplexing of DPDCHs is 4 according to a conventionalmethod.

FIG. 35 shows a configuration of data channel multiplex transmission inuplink enhancement (case 1).

FIG. 36 shows a configuration of data channel multiplex transmission inuplink enhancement (case 2).

FIG. 37 shows a flowchart for determining assignment of channelizationcodes by calculating gain factors according to a sixth embodiment.

FIG. 38 shows a flowchart for determining assignment of channelizationcodes by calculating gain factors according to a seventh embodiment.

FIG. 39 shows a flowchart for determining assignment of channelizationcodes based on a magnitude of SF when there is no HS-DPCCH according toan eighth embodiment.

FIG. 40 shows an example of assignment of channelization codes based ona magnitude of SF when there is no HS-DPCCH according to the eighthembodiment.

FIG. 41 shows a code tree of channelization codes at an I axis accordingto the eighth embodiment.

FIG. 42 shows a code tree of channelization codes at a Q axis accordingto the eighth embodiment.

FIG. 43 shows an example of assignment of channelization codes based ona magnitude of SF when there is an HS-DPCCH according to the eighthembodiment.

FIG. 44 shows an example of assignment of channelization codes based ona magnitude of SF when there is an HS-DPCCH according to the eighthembodiment.

FIG. 45 is a table showing a configuration of channelization codesaccording to the eighth embodiment.

FIG. 46 shows a flowchart for determining assignment of channelizationcodes when data channels having different SFs are multiplexed accordingto the eighth embodiment.

FIG. 47 shows a flowchart for determining assignment of channelizationcodes when data channels having different SFs are multiplexed accordingto the eighth embodiment.

PREFERRED EMBODIMENTS FOR CARRYING OUT THE INVENTION

Data channels discussed in the following embodiments show a DPDCH and anE-DPCCH. Further, for a DPDCH discussed in the following embodiments,cases in which DCH is superimposed, E-DCH is superimposed, E-DPCCH issuperimposed, HS-DPCCH is superimposed, multiple channels of DCH, E-DCH,E-DPCCH, and HS-DPCCH are multiplexed and superimposed are considered.

Data channels having different gain factors mean both or one of channelswhen kinds of the channels are different such as a DPDCH and an E-DPCCH;and when performance of the channels are different depending on channels(in this case, DCH or E-DCH) superimposed on a certain channel (a DPDCH,for example) such as a DPDCH superimposing DCH and a DPDCH superimposingE-DCH.

A gain factor is an example of factors. The factors can be the gainfactor itself and also values to be multiplied to the gain factor. Inthe following, the gain factor is also referred to as a.

Embodiment 1

FIG. 1 shows a CDMA terminal (a communication apparatus such as acellular phone) according to the present embodiment. At a transmittingside, a protocol processing unit 900 sets a transmission channel. Next,a transmitting unit 901 performs a process of the transmission channel.And then, a modulating unit 902 carries out multiplexing and spreadingof codes using a scrambling code generator 903 and a channelization codegenerator 904 as shown in FIG. 29. A controlling unit 905 setschannelization codes output from the channelization code generator 904.A signal modulated by the modulating unit 902 is converted into ananalog signal by a digital/analog (D/A) converter 906, changed into anRF (Radio Frequency) signal by a frequency changing unit 907, amplifiedto desired electric power by a power amplifying unit 908, andtransmitted via an antenna 909. At a receiving side, a feeble signalreceived by the antenna 909 is amplified by a low noise amplifying unit910, changed to a base-band signal by a frequency changing unit 911,demodulated by a receiving unit 912, and transferred to the protocolprocessing unit 900.

FIG. 2 shows a CDMA base station (Node-B) which transmits/receives datato/from a CDMA terminal in the present embodiment. At the transmittingside, a signal to be transmitted is transferred from a base stationcontrolling apparatus 3100 to a transmitting unit 3101, the signal ismodulated in the transmitting unit 3101, changed into an RF (RadioFrequency) signal by a frequency changing unit 3103, amplified todesired electric power by a power amplifying unit 3104, and transmittedfrom an antenna 3105. At the receiving side, a feeble signal received atthe antenna 3105 is amplified by a low noise amplifying unit 3106,changed into a base-band signal by a frequency changing unit 3107, andconverted into a digital signal by an analog/digital (A/D) converter3108. And then, in a demodulating unit 3109, demodulation is carried outusing a channelization code generator 3110 and a scrambling codegenerator 3111. A controlling unit 3102 sets channelization codes outputfrom the channelization code generator 3110. And then, in a receivingunit 3112, decoding is carried out by the channel, and the decodedsignal is transferred to the base station controlling apparatus 3100.

FIG. 3 is a block diagram showing a controlling unit 905 (or thecontrolling unit 3102; this is the same hereinafter) provided at acommunication apparatus according to the first embodiment of theinvention. The controlling unit 905 inputs information necessary toassign the channels. For example, the number, the kind, the performance,and the gain factors, etc. of channels to be multiplexed to channels ofI, Q are input. The controlling unit 905 includes a CPU (centralprocessing unit) 10. The CPU 10 controls an operation of the controllingunit 905 and is connected to each unit with buses to implement anoperation of each part or allows each part to implement the operation.Further, the CPU 10 is connected to a memory 15 via a bus. The memory 15is, for example, a ROM (Read Only Memory), a RAM (Random Access Memory),an FDD (Flexible Disk Drive), a CDD (Compact Disk Drive), a magneticdisk drive, an optical disk drive, and so on. A RAM is an example ofvolatile memories. A ROM, an FDD, a CDD, a magnetic disk drive, and anoptical disk drive are examples of non-volatile memories.

Data and information handled by each part of the controlling unit 905shown in FIG. 3 are stored in the memory 15 and recorded and read byeach part of the controlling unit 905. Further, an operating system(OS), a window system, a group of programs, a group of files (database)are stored in the memory 15. The group of programs is executed by a CPU,an OS, and the window system. Each part of the controlling unit 905 canbe configured partly or entirely by programs which can operate on acomputer. Or it can be implemented in a firmware stored in a ROM. Or itcan be implemented in software, hardware, or a combination of software,hardware, and firmware. In the group of programs, programs that make theCPU implement processing which are explained in the explanation ofembodiment as “—unit” are stored.

Each part of the controlling unit 905 will be explained. The controllingunit 905 includes a code combination creating unit 11 that creates allpossible combinations of the channelization codes. Further, thecontrolling unit 905 includes an inter-chip phase variation calculatingunit 12 that calculates each phase variation between a plurality ofchips. Further, the controlling unit 905 includes a code combinationdetermining unit 13 that obtains a combination of the channelizationcodes of which a sum of overshoot generated by each phase variationbetween the plurality of chips that is calculated by the inter-chipphase variation calculating unit 12, is small by a calculation todetermine as a combination of codes for use. Further, the controllingunit 905 includes a code assignment instructing unit 14 that instructsthe assignment of the channelization codes to the channelization codegenerator 904 based on the combination of codes determined by the codecombination determining unit 13. The inter-chip phase variationcalculating unit 12 obtains phase variations between the first andsecond chips and the third and fourth chips, respectively. Further, thecode combination determining unit 13 determines a combination of codesin which the phase variation between the first and second chips and thatof the third and fourth chips are close to 0 degrees or 180 degrees,respectively, as the combination of codes for use.

FIGS. 4, 5, and 6 show diagrams of multiplex transmission of uplink datachannels for transmitting data from a communication apparatus in thefirst embodiment to a base station. In this embodiment, not only aDPDCH, an E-DPCCH which is a control channel described in TR25.896 isalso treated as a data channel in case of code assignment. Therefore,the data channels in each figure include an E-DPCCH which is a controlchannel other than DPDCHs. Further, cases are considered in which DPDCHssuperimpose DCH, E-DCH, E-DPCCH, HS-DPCCH, and also plural multiplexchannels out of DCH, E-DCH, E-DPCCH, HS-DPCCH. Further, in case of anHS-DPCCH, three methods can be considered: a method in whichmultiplexing is done to both I and Q based on the number of multiplexeddata channels such as the present specification as shown in FIG. 4; amethod in which multiplexing is done fixedly at the Q side as shown inFIG. 5; and a method in which multiplexing is done fixedly at the I sideas shown in FIG. 6. The proposed technique can be applied to any of thethree methods. It is also applicable to a case in which there is noHS-DPCCH. Further, the number of data channels to be multiplexed is upto six (the number of multiplexing N≦6) similarly to the conventionalart. Gain factors β₁ through β₈ shown in the figure are 0≦β≦1. Further,both cases are considered in which there are channels shown by a brokenline and there are no such channels. Namely, it is applicable regardlessof the number N of data channels (the number of multiplexing N), kindsof data channels, and performance of data channels. Yet further, it isapplicable to both cases in which the assignment of channelization codesis determined based on an initial number of multiplexing and theperformance of data channels and the assignment is kept to the end, andin which the assignment of channelization codes is determined for eachframe.

In the first embodiment, the assignment of channelization codes isdetermined in the following way. For all possible combinations ofchannelization out of the given data channels and control channels, atransition θ₁ (phase variation α) from the first chip to the second chipand a transition θ₂ (phase variation β) are obtained. As for eachtransition, in case of 0 degrees or 180 degrees, PAR becomes small sincethe overshoot is the smallest, and in case of 90 degrees, PAR becomeslarge since the overshoot is the largest. Therefore, it is preferable toassign the channelization codes so that transitions should be close to 0degrees or 180 degrees and also far from 90 degrees. That is, it ispossible to obtain the most ideal combination by obtaining a combinationwhich makes sin² θ₁+sin² θ₂ the smallest.

FIG. 7 is a flowchart showing a way to assign the channelization codesimplemented by the controlling unit 905 according to the firstembodiment. First, at STEP1300, the code combination creating unit 11defines the number of combinations of the channelization codes as Num,defines a set of combinations of all channelization codes as T,initializes D to 2, and stores in the memory 15. At STEP1301, the codecombination creating unit 11 sets Num=Num−1 and selects an arbitrarycombination from T, define it as C1, deletes the combination selectedfrom T, and updates the memory 15. At STEP1302, the inter-chip phasevariation calculating unit 12 obtains a transition θ₁ from the firstchip to the second chip in case of assigning the combination C₁ to thechannels and stores in the memory 15. Also at STEP1303, the inter-chipphase variation calculating unit 12 obtains the transition θ₂ from thethird chip to the fourth chip in case of assigning the combination C₁ tothe channels and stores in the memory 15 similarly to STEP1302. AtSTEP1304, the code combination determining unit 13 sets D₁=sin² θ₁+sin²θ₂ and stores in the memory 15. At STEP1305, the code combinationdetermining unit 13 judges if D₁<D. If D₁<D, STEP1306 is implemented. Ifnot D₁<D, STEP1307 is implemented. At STEP1306, the code combinationdetermining unit 13 sets C=C₁ and D=D₁ and stores in the memory 15. AtSTEP1307, if Num>0, the operation returns to STEP1301. If Numb≦0,STEP1308 is implemented. At STEP1308, the code assignment instructingunit 14 indicates C stored in the memory 15 as an optimal combinationand based on this, assigns the channelization codes to each datachannel. The code assignment instructing unit 14 notifies thechannelization code generator 904 of the assignment of channelizationcodes.

According to the present embodiment, a combination of the channelizationcodes, overshoot caused by which is small, can be obtained automaticallyby calculation. Further, the combination of channelization codes isobtained, with which the phase variation between the first and secondchips and the phase variation between the third and fourth chips areclose to 0 degrees or 180 degrees, respectively, so that the phasevariation becomes far from 90 degrees and the overshoot can beeliminated. Further, since the phase variation α between the first andsecond chips of the I and Q channels and the phase variation β betweenthe third and fourth chips of the I and Q channels are obtained, it ispossible to reduce the overshoot due to the phase variation between anodd-numbered chip and an even-numbered chip.

Embodiment 2

FIG. 8 is an explanatory drawing of multiplex transmission of uplinkdata channels for transmitting data from a communication apparatus inthe second embodiment to a base station. In this embodiment, other thanDPDCHs, an E-DPCCH which is a control channel is also treated as a datachannel in case of code assignment. Therefore, data channels in thefigure include an E-DPCCH which is a control channel other than DPDCHs.In the second embodiment, a case without an HS-DPCCH is considered as acontrol channel to be multiplexed. Further, cases are considered inwhich DPDCHs superimpose DCH, E-DCH, E-DPCCH, HS-DPCCH, and also pluralchannels out of DCH, E-DCH, E-DPCCH, HS-DPCCH by multiplexing them. Gainfactors β₁ through β₆ are 0≦β≦1. Further, as for a part shown by abroken line in the figure a case without data channel is alsoconsidered. Namely, it is applicable regardless of the number N of datachannels, kinds of data channels, and performance of data channels. Yetfurther, it is applicable to both cases in which the assignment ofchannelization codes is determined based on the initial number ofmultiplexing and the performance and the assignment is kept to the end,and in which the assignment of channelization codes is determined foreach frame.

In the first embodiment, for each combination of channelization codes,phase variations among a plurality of chips are respectively calculated,and a combination of channelization codes, with which a sum ofovershoots caused by each of the phase variations among the plurality ofchips is small, is obtained by calculation. More concretely, in order toobtain a combination of channelization codes of which a sum of theovershoots is small, a combination of channelization codes of which eachof a phase variation between the first chip and the second chip and aphase variation between the third chip and the fourth chip are close to0 degrees or 180 degrees, respectively, is obtained. On the other hand,in the second embodiment discussed below, the channelization codes areassigned to channels from the channel having a large gain factor, and aphase variation from an odd-numbered chip to an even-numbered chip ismade close to 0 degrees or 180 degrees as much as possible, and alsomade far from 90 degrees as much as possible. Further, in the secondembodiment, using a fact that a gain factor of a DPCCH is very small, itis assumed that the DPCCH does not affect a phase variation.

A phase variation from an odd-numbered chip to an even-numbered chip incase of using only channelization codes C_(4,0) and C_(4,1) alwaysmaintains 0 degrees even if the gain factor is changed. This is verifiedby the following expression. Since channels of both the I side and the Qside use only C_(4,0)=(1,1,1,1) and C_(4,1)=(1,1,−1,−1), the followingexpressions can be applied regardless of kinds of channels, values ofgain factors, and the number of multiplexing. β₁ through β₄ below arereal numbers.I=β ₁+β₂, β₁+β₂, β₁−β₂, β₁−β₂Q=β ₃+β₄, β₃+β₄, β₃−β₄, β₃−β₄

As discussed, a phase variation from an odd-numbered chip to aneven-numbered chip is 0 degrees. Further, the phase variation from anodd-numbered chip to an even-numbered chip in case of using onlychannelization codes C_(4,2) and C_(4,3) is always 180 degrees even ifthe gain factor is changed. Since channels of both I side and Q side useonly C_(4,2)=(1,−1,1,−1) and C_(4,3)=(1,−1,−1,1), the followingexpressions can be applied regardless of kinds of channels, values ofgain factors, and the number of multiplexing. β₁ through β₄ below arereal numbers.I=β ₁+β₂, −β₁−β₂, β₁−β₂, −β₁+β₂Q=β ₃+β₄, −β₃−β₄, β₃−β₄, −β₃+β₄

As discussed, a phase variation from an odd-numbered chip to aneven-numbered chip is 180 degrees.

When the channelization codes C_(4,0) and C_(4,1) and the channelizationcodes C_(4,2) and C_(4,3) are included in the I side or the Q side, thephase variation becomes close to 90 degrees. Accordingly, it ispreferable not to mix C_(4,0), C_(4,1) and C_(4,2), C_(4,3). Concretely,it is necessary to assign the channelization codes using a combinationin which both the I side and the Q side use only C_(4,0) or C_(4,1) or acombination in which both the I side and the Q side use only C_(4,2) orC_(4,3). It is assumed that a sum of the gain factors of data channelsto which C_(4,0) or C_(4,1) is assigned is β₀₁, and a sum of the gainfactors of data channels to which C_(4,2) or C_(4,3) is assigned is β₂₃.In order not to make θ 90 degrees, β₀₁ is made large and β₂₃ is madesmall, or β₂₃ is made large and β₀₁ is made small. That is, it iseffective to assign C_(4,0) and C_(4,1) or C_(4,2) and C_(4,3) tochannels from a channel having a gain factor being as large as possible.In this embodiment, data channels having different gain factors are bothor one of cases in which kinds of the channels are different such as anE-DPCCH and a DPDCH, and in which performance of the channels aredifferent depending on channels such as the same DPDCHs superimposingDCH and superimposing E-DCH.

FIG. 9 shows a block diagram of the controlling unit 905 according tothe second embodiment. The controlling unit 905 includes a codeassigning unit by gain factor 21 (also called as a code assigning unitby factor) for assigning predetermined channelization codes to channelsfrom a channel having a large gain factor based on the gain factors β₁through β₆ obtained by calculation of the protocol processing unit 900.Further, a remaining code assigning unit 22 is also included forassigning channelization codes other than the predeterminedchannelization codes to channels to which no channelization codes areassigned by the code assigning unit by gain factor 21. Further, a codeassignment instructing unit 14 is also included for instructing theassignment of channelization codes assigned by the code assigning unitby gain factor 21 and the remaining code assigning unit 22.

FIG. 10 is a flowchart showing a way to assign the channelization codesin the second embodiment. At STEP1500, the code assigning unit by gainfactor 21 judges if the number N of multiplex data channels is equal toor less than three. If the number N of multiplexing is not more thanthree, STEP1501 is implemented; the number N of multiplexing is at leastfour, STEP1502 is implemented. At STEP1501, the code assigning unit bygain factor 21 assigns the channelization code C_(4,0) or C_(4,1) to alldata channels, or in another way assigns the channelization code C_(4,2)or C_(4,3) to all data channels, and stores in the memory 15. AtSTEP1502, the code assigning unit by gain factor 21 assigns one of thechannelization codes C_(4,2) or C_(4,3) to two data channels havinglargest gain factors out of the data channels to be multiplexed at the Iside and stores in the memory 15. At STEP1503, the remaining codeassigning unit 22 judges if there is any data channel at the I side towhich no channelization code is assigned. If there is, STEP1504 isimplemented. If not, STEP1505 is implemented. At STEP1504, the remainingcode assigning unit 22 assigns one of C_(4,0) and C_(4,1) to datachannels at the I side to which no channelization code is assigned andstores in the memory 15.

At STEP1505, the code assigning unit by gain factor 21 assigns thechannelization codes to the data channels to be multiplexed at the Qside in the same manner to the I side. Namely, the code assigning unitby gain factor 21 assigns one of the channelization codes C_(4,2) andC_(4,3) to two data channels at the Q side having a large gain factorand stores in the memory 15. At STEP1506, the remaining code assigningunit 22 judges if there is any data channel at the Q side to which nochannelization code is assigned. If there is, STEP1507 is implemented.If there is not, the operation terminates. At STEP1507, the remainingcode assigning unit 22 assigns the channelization code C_(4,1) to datachannels at the Q side to which no channelization code is assigned andstores in the memory 15. This embodiment brings an effect that theovershoots of two channels having large gain factors can be removed.

Embodiment 3

In the second embodiment, the assignment of channelization codes iscarried out to channels from a channel having a large gain factor, sothat a phase variation from an odd-numbered chip to an even-numberedchip should be made close to 0 degrees or 180 degrees and far from 90degrees as much as possible. More concretely, the phase variationbecomes close to 90 degrees when the channelization codes C_(4,0) andC_(4,1) and the channelization codes C_(4,2) and C_(4,3) are mixed atthe I side or the Q side. In the above second embodiment, thechannelization codes are assigned by, for example, combining onlyC_(4,0) or C_(4,1) at both I side and Q side; or combining only C_(4,2)or C_(4,3) at both I side and Q side. In the third embodiment that willbe explained below, a way to assign the channelization codes isdetermined by a kind and performance of data channel, namely, dataamount of data channel instead of the gain factor of data channel. Dataamount of data channel is different depending on kinds of data channelsuch as, for example, data channels of an E-DPCCH and a DPDCH. Or, evenif the kinds of data channels are the same, it is different depending onchannels that the data channels superimpose. Concretely, a DPDCH thatsuperimposes DCH and a DPDCH that superimposes E-DCH are the same kindof DPDCHs; however, the performances of them are different depending onthe channels that they superimpose. Therefore, the data amount of datachannel is also different according to the performance of channel.

In the following explanation, the channelization codes are assigned onthe assumption that data amount of each data channel is as follows:

(1) Since data amount of a DPCCH is small, the data amount of a DPCCHdoes not affect the assignment of channelization codes;

(2) As for variation due to kinds of channels, data amount of an E-DPCCHis larger than that of a DPDCH;

(3) As for variation due to performance of channels, data amount of DCH,E-DCH, E-DPCCH, and HS-DPCCH superimposed on DPDCHs are like:E-DPCCH≧E-DCH≧DCH=HS-DPCCH;(4) Data amount of a DPDCH that superimposes multiple channels of DCH,E-DCH, E-DPCCH, and HS-DPCCH is larger than that of a DPDCH thatsuperimposes only one of DCH, E-DCH, E-DPCCH, and HS-DPCCH;(5) Among DPDCHs that respectively superimpose multiple channels of DCH,E-DCH, E-DPCCH, and HS-DPCCH, data amount of a DPDCH that superimposesmore number of multiple channels is larger;(6) Among DPDCHs that respectively superimpose the same number ofmultiple channels of DCH, E-DCH, E-DPCCH, and HS-DPCCH, if one includesE-DPCCH, data amount of a DPDCH that includes E-DPCCH is larger; and(7) Among DPDCHs that respectively superimpose the same number ofmultiple channels of DCH, E-DCH, E-DPCCH, and HS-DPCCH, when noneincludes E-DPCCH, data amount of a DPDCH that does not include E-DCH issmaller; or if both include E-DCH, data amount of both DPDCHs are thesame.

FIG. 11 shows a block diagram of a controlling unit 905 of acommunication apparatus depending on the third embodiment. Thecontrolling unit 905 includes a code assigning unit by data amount 31for assigning predetermined channelization codes to channels from achannel of which data amount is large. Further, a remaining codeassigning unit 22 is provided for assigning channelization codes otherthan the predetermined channelization codes to channels to which nochannelization codes have been assigned by the code assigning unit bydata amount 31. Further, a code assignment instructing unit 14 forinstructing assignment of the channelization codes assigned by the codeassigning unit by data amount 31 and the remaining code assigning unit22. FIGS. 12 through 16 are explanatory drawings of multiplextransmission of uplink data channels in which the communicationapparatus according to the third embodiment transmits data to the basestation with multiplexed data channels of which the number N ofmultiplexing is 2 through 6. As shown in FIGS. 12 through 14, when anHS-DPCCH is not included and the number N of multiplexing is no morethan 4, code assignment does not change based on kinds of data channels,and the existing method disclosed in JP2002-33716 can be applied.

As shown in FIGS. 15 and 16, when the number of multiplexing is N≧5, away to assign the codes by the code assigning unit by data amount 31varies according to kinds of channels. The code assigning unit by dataamount 31, as shown in FIG. 15, assigns channelization codes C_(4,2) orC_(4,3) to a data channel of which the data amount is large such asDPDCH, on which E-DCH, DCH, and E-DPCCH are multiplexed or DPDCH₅ thatsuperimposes E-DCH among channels at the I side. The remaining codeassigning unit 22 assigns C_(4,0) or C_(4,1) to a data channel of whichthe data amount is relatively small such as DPDCH₃ that superimposesonly DCH. When the number of multiplexing N=5, C_(4,2) and C_(4,3) areassigned to channels at the Q side regardless of data amount (regardlessof gain factors) of the data channels.

The code assigning unit by data amount 31 assigns, as shown in FIG. 16,the channelization codes C_(4,2) or C_(4,3) to data channels of whichdata amount is large such as DPDCH₅ that superimposes E-DCH amongchannels at the I side. When the kinds of channels are the same such asDPDCH₁ and DPDCH₃, either of C_(4,2) and C_(4,3) is assigned to one ofthem, and to the remaining data channel, C_(4,0) or C_(4,1) is assigned.Further, the code assigning unit by data amount 31 assigns either of thechannelization codes C_(4,2) and C_(4,3) to a data channel of which dataamount is large such as DPDCH₄ that superimposes E-DCH or DCH amongchannels at the Q side. The remaining code assigning unit 22 assignseither of C_(4,0) and C_(4,1) to data channels of which the data amountis small such as DPDCH₂ that superimposes only DCH. As discussed above,the present embodiment brings an effect that the overshoot of channelsof which data amount is large can be removed.

Embodiment 4

FIGS. 17, 18, and 19 are explanatory drawings of multiplex transmissionof uplink data channels in which the communication apparatus accordingto the fourth embodiment transmits data to the base station. In thisembodiment, other than DPDCHs, an E-DPCCH that is a control channel istreated as a data channel in case of assigning codes, so that the datachannels shown in the figures include an E-DPCCH that is a controlchannel as well as DPDCHs. In the second embodiment, a case without anHS-DPCCH is explained; in the fourth embodiment that will be explainedbelow, another case with an HS-DPCCH is considered. Further, cases areconsidered, in which a DPDCH superimposes DCH, in which a DPDCHsuperimposes E-DCH, in which a DPDCH superimposes E-DPCCH, and in whicha DPDCH superimposes multiple channels of DCH, E-DCH, and E-DPCCH. Inthe figures, gain factors β₁ through β₆ are 0≦β≦1. Further, a casewithout any data channel is also considered as illustrated by a partshown with a broken line in the figure. That is, it is applicableregardless of the number N of multiplexed data channels, kinds ofchannels, and performance of channels. Further, a proposed method can beapplied to any of three ways of fixing an HS-DPCCH: a way in which anHS-DPCCH is multiplexed to either the I or Q side according to thenumber of multiplexed data channels as shown in FIG. 17; another way inwhich the HS-DPCCH is fixed to the Q side as shown in FIG. 18; and theother way in which the HS-DPCCH is fixed to the I side as shown in FIG.19. In case of uplink enhancement, it is not decided which code isassigned to the HS-DPCCH. In specification, C_(256,32) is assigned tothe HS-DPCCH when the number of multiplexed channels is odd, andC_(256,1) is assigned to the HS-DPCCH when the number N of multiplexedchannels is even.

A way to assign the channelization codes in case of uplink enhancementis not predetermined; however, in the present embodiment, it is assumedthat C_(256,1) is assigned when the HS-DPCCH is at the I side, andC_(256,32) is assigned when the HS-DPCCH is at the Q side. Whichevercode is assigned, they are the same as C_(4,0) when it is considered bya unit of 4 chips. Accordingly, when the HS-DPCCH is at the I side,C_(4,0) cannot be used as a channelization code at the I side.

Similar to the second embodiment, in the fourth embodiment,channelization codes are assigned to channels from the channel having alarge gain factor. The channelization codes are assigned by acombination of using only C_(4,0) or C_(4,1) at both I and Q sides or acombination of using only C_(4,2) or C_(4,3) at both I and Q sides, sothat a phase variation from an odd-numbered chip to an even-numberedchip should become close to 0 degrees or 180 degrees and far from 90degrees as much as possible. Further, in the fourth embodiment, it isassumed that a DPCCH does not affect a phase variation by using a factthat the gain factor of a DPCCH is very small. In this embodiment,channels of which gain factors are different mean both or one of casesin which kinds of channels are different such as an E-DPCCH and a DPDCH,and in which performance of channels are different such as a DPDCH thatsuperimposes DCH and the same a DPDCH that superimposes E-DCH.

Further, an E-DPCCH is treated similarly to a DPDCH that superimposesE-DCH. Further, in this embodiment, the gain factor of an HS-DPCCH isconsidered almost the same as a DPDCH that superimposes DCH, consideringa fact that the gain factor of the HS-DPCCH becomes extremely large whenit exists at a cell edge. Because of this, due to an effect of theHS-DPCCH, if the HS-DPCCH is at the I side even if the number ofmultiplexing is the same, that is, three, there is high possibility toimprove PAR when the channelization code C_(4,2) or C_(4,3) is assignedto all channels, and when the channelization code C_(4,0) or C_(4,1) isassigned to all channels if the HS-DPCCH is at the Q side.

FIG. 20 shows a block diagram of a controlling unit 905 provided at acommunication apparatus according to the fourth embodiment. The codeassigning unit by gain factor 21 includes a prohibited code judging unit41 for, when there is a specific kind of channel to which a specificchannelization code is assigned, detecting a channelization code whichhas a correlation with the specific channelization code assigned to thespecific kind of channel, and prohibiting the channelization code whichis detected to have a correlation from being assigned. For example, theprohibited code judging unit 41 judges if the HS-DPCCH is at the I sideor not. When the HS-DPCCH is at the I side, it is determined thatC_(4,0) should not be used as a channelization code at the I side.

When the prohibited code judging unit 41 judges that the HS-DPCCH is atthe Q side, a process shown in FIG. 21 is carried out to assign thechannelization codes. An explanation for the process of FIG. 21 will beomitted, as the process is the same as that has been explained usingFIG. 10.

On the other hand, if the prohibited code judging unit 41 judges theHS-DPCCH is at the I side, a process which will be explained below andshown in FIG. 22 is carried out to assign the channelization codes. InFIG. 22, at STEP2500, the code assigning unit by gain factor 21 judgesif the number N of multiplexed data channels is 2. If the number N ofmultiplexing is 2, a process of STEP2501 is implemented; if the number Nof multiplexing is at least 3, a process of STEP2502 is implemented. AtSTEP2501, the code assigning unit by gain factor 21 assigns thechannelization code C_(4,1) to all data channels, and stores in thememory 15. At STEP2502, the code assigning unit by gain factor 21 judgesif the number N of multiplexed data channels is 3. If the number N ofmultiplexing is 3, a process of STEP2503 is implemented; if the number Nof multiplexing is at least 4, a process of STEP2504 is implemented. AtSTEP2503, the code assigning unit by gain factor 21 assigns thechannelization code C_(4,2) or C_(4,3) to all data channels and storesin the memory 15. At STEP2504, the code assigning unit by gain factor 21assigns the channelization code C_(4,2) or C_(4,3) to two DPDCHs havinglargest gains among existing data channels to be multiplexed at the Iside and stores in the memory 15. At STEP2505, the remaining codeassigning unit 22 judges if there is any data channel to which nochannelization code is assigned at the I side. If there is, a process ofSTEP2506 is implemented. If there is not, a process of STEP2507 isimplemented. At STEP2506, the remaining code assigning unit 22 assignsthe channelization code C_(4,1) to a DPDCH to which no channelizationcode is assigned and stores in the memory 15. At STEP2507, the codeassigning unit by gain factor 21, similarly to the I side, assigns thechannelization code C_(4,2) or C_(4,3) to two data channels havinglargest gains among existing data channels to be multiplexed at the Qside and stores in the memory 15. At STEP2508, the remaining codeassigning unit 22 judges if there is any data channel to which nochannelization code is assigned at the Q side. If there is, a process ofSTEP2409 is implemented. If there is not, the operation terminates.

At STEP2509, the remaining code assigning unit 22 assigns thechannelization code C_(4,1) to data channels at the Q side to which nochannelization code is assigned and stores in the memory 15. Here,C_(4,0) is not used as a channelization code. According to the presentembodiment, it is judged if there exists a specific channel, and codesthat have little correlation with the code which is determined to beused for the specific channel are used. Therefore, it is possible toreduce the overshoot.

Embodiment 5

In the third embodiment, the assignment of channelization codes isdetermined based on the kind and performance of the data channels,namely, data amount of the data channels instead of gain factors of thedata channels. However, in the third embodiment, a case is notconsidered, in which an HS-DPCCH is provided as an independent controlchannel. Hereinafter, in the fifth embodiment, another way to determinethe assignment of channelization codes will be explained when anHS-DPCCH is provided as an independent control channel. In the presentembodiment, data amount of each data channel is also judged based on (1)through (7) discussed in the third embodiment, and the channelizationcodes are assigned.

FIG. 23 shows a block diagram of a controlling unit 905 of acommunication apparatus according to the fifth embodiment. The codeassigning unit by data amount 31 includes a prohibited code judging unit41 for, when there is a specific kind of channel to which a specificchannelization code is assigned, detecting a channelization code whichhas a correlation with the specific channelization code assigned to thespecific kind of channel, and prohibiting the channelization code whichis detected to have a correlation from being assigned. For example, theprohibited code judging unit 41 judges whether an HS-DPCCH is at the Iside or not. When an HS-DPCCH is at the I side, it is determined not touse C_(4,0) as a channelization code at the I side. The other points arethe same as the third embodiment.

FIGS. 24 through 28 show ways of assignment according to the fifthembodiment when the number N of multiplex data channels is 2 to 6,respectively. The code assigning unit by data amount 31 limits theassignment of channelization codes to C_(4,0) or C_(4,1) when the numberof multiplexing N=2 as shown in FIG. 24. Further, the code assigningunit by data amount 31 also limits the assignment of channelizationcodes to C_(4,0) or C_(4,1) when the number of multiplexing N=3 and theHS-DPCCH is at the Q side as shown in FIG. 25. The code assigning unitby data amount 31 assigns the channelization codes C_(4,2) or C_(4,3)when the number N of, multiplexing is 4 as shown in FIG. 26 andsimilarly to the second embodiment and stores in the memory 15.

As shown in FIGS. 27 and 28, in case of the number of multiplexing N≧5,the assignment of codes varies according to a kind of channels. The codeassigning unit by data amount 31 assigns, as shown in FIG. 27, as forthe channels at the I side, the channelization codes C_(4,2) or C_(4,3)to the data channels of which data amount is large such as DPDCH₃ thatsuperimposes E-DCH or DPDCH₅ with E-DCH and DCH multiplexed, and storesin the memory 15. The remaining code assigning unit 22 assigns C_(4,0)or C_(4,1) to the data channels of conventional kind of which the dataamount is small such as DPDCH, that superimposes only DCH, and stores inthe memory 1. In case of the number of multiplexing N=5, C_(4,2) orC_(4,3) is assigned to the channels at the Q side regardless of the dataamount, and stores in the memory 15. The code assigning unit by dataamount 31 assigns, as shown in FIG. 28, as for the channels at the Iside, the channelization codes C_(4,2) or C_(4,3) to the data channelsof which data amount is large such as DPDCH₃ and DPDCH₅ that superimposeE-DCH, and stores in the memory 15. The remaining code assigning unit 22assigns C_(4,1) to the data channels of which the data amount is smallsuch as DPDCH, that superimposes only DCH, and stores in the memory 15.Further, the code assigning unit by data amount 31 assigns, as for thechannels at the Q side, the channelization codes C_(4,2) or C_(4,3) tothe data channels of which data amount is large such as DPDCH₄ thatsuperimposes E-DCH or DPDCH₆ with E-DCH and DCH multiplexed, and storesin the memory 15. The remaining code assigning unit 22 assigns C_(4,1)to the data channels of which the data amount is small such as DPDCH₂that superimposes only DCH, and stores in the memory 15. From FIG. 28,it is understood that the channelization code C_(4,0) cannot be used dueto influence of the HS-DPCCH.

According to the present embodiment, it is judged if there exists aspecific channel, and codes that has little correlation with the codewhich is determined to be used for the specific channel are used.Therefore, it is possible to reduce the overshoot.

Embodiment 6

A data channel that will be discussed in the embodiment means an E-DPCCH(Enhanced DPDCH) and does not include a DPDCH. Further, a DPDCH in thesixth embodiment has considerably small data amount compared with anE-DPDCH, and when the spreading factor is sf (>4), the channelizationcode C_(sf,SF/4) is used. For example, in case of 64 kbps, thechannelization code C_(16,4) is used. Further, in this embodiment, it isassumed that as DPDCHs, a data channel with SF=2 and a data channel withSF=4 are multiplexed.

Configurations of a communication apparatus and a controlling unitprovided at the communication apparatus according to the presentembodiment are the same as ones of the first embodiment shown in FIGS. 1and 3.

In this embodiment, it is explained that the first embodiment can beaccomplished when the smallest SF of the data channels is 2. When SF is2, if one piece of data is spread, the data becomes two chips.Accordingly, different from the first embodiment, the third chip and thefourth chip are a result obtained from spreading data which is differentfrom the data spread into the first chip and the second chip. Then, incase of SF=2, the phase variation should be considered for only atransition from the first chip to the second chip. Here, it is definedthat the phase variation from the first chip to the second chip is θ.Therefore, in case of SF=2, a combination which is the closest to theoptimal can be obtained by obtaining a combination of the channelizationcodes that minimizes sin² θ. The chip transition means to move a signalpoint after spreading is done by the channelization codes, and alsomeans variation of constellations.

FIG. 37 is a flowchart showing assignment of the channelization codesimplemented by the controlling unit 905 according to the sixthembodiment. First, at STEP3700, the code combination creating unit 11defines the number of combinations of channelization codes as Num, a setof combinations of all channelization codes as T, and a magnitude of thecurrent overshoot as D, and the code combination creating unit 11initializes D to the maximum value 1 and stores in the memory 15. AtSTEP3701, the code combination creating unit 11 sets Num=Num−1, selectsan arbitrary combination from T to define as C₁, deletes the combinationselected from T from the memory 15, and updates the memory 15. AtSTEP3702, the inter-chip phase variation calculating unit 12 obtains aphase variation θ from the first chip to the second chip in case ofassigning the combination C₁ to the channels and stores in the memory15. At STEP3703, the code combination determining unit 13 defines aparameter for obtaining the magnitude of overshoot for the combinationC₁ as D₁=sin² θ and stores in the memory 15. At STEP3704, the codecombination determining unit 13 judges if the overshoot for C₁ issmaller than D. Namely, D₁<D is examined. If D₁<D, ST3705 isimplemented. If not D₁<D, STEP3706 is implemented. At STEP3705, the codecombination determining unit 13 replaces C with another combination ofthe channelization codes which creates smaller overshoot. That is, itsets C=C₁ and D=D₁ and stores in the memory 15. At STEP3706, if Num>0,the operation returns to STEP3701. If Num≦0, STEP3707 is implemented. AtSTEP3707, the code assignment instructing unit 14 defines C stored inthe memory 15 as the combination which creates the smallest overshoot,and the code assignment instructing unit 14 assigns the channelizationcodes to each data channel based on this. The code assignmentinstructing unit 14 notifies the channelization code generator 904 ofthe assignment of channelization codes.

The present embodiment enables to automatically obtain the combinationof channelization codes which generates small overshoot by calculation.Further, the combination of channelization codes is obtained, of whichthe phase variation from the first chip to the second chip is close to 0degrees or 180 degrees and thus the phase variation is far from 90degrees, so that the overshoot can be eliminated. Further, the phasevariation from the first chip to the second chip of the I channel andthe Q channel is obtained, so that the overshoot caused by the phasevariation between an odd-numbered chip and an even-numbered chip can bereduced.

Embodiment 7

Configurations of a communication apparatus according to the presentembodiment and a controlling unit provided at the communicationapparatus are the same as ones of the first embodiment shown in FIGS. 1and 3.

In the following, it is explained that the first and the sixthembodiments can be established even if the smallest SF of the datachannels is other than 2 or 4 in the present embodiment. Obtaining bycalculation similarly to the first and the sixth embodiments isconsidered when there are data channels (E-DPDCHs) of which SFs aredifferent. For obtaining by calculation, only a transition between chipsas many as the smallest SF is considered, since a transition betweenchips for one piece of data should be considered. When the smallest SFof all data channels (E-DPDCHs) is defined as sf, and a transition fromthe (2m−1)th chip to the 2mth, chip is defined as θ_(m), thechannelization codes are assigned so as to minimizesin² θ₁+sin² θ₂+ . . . +sin² θ_(sf/2).

FIG. 38 is a flowchart showing assignment of channelization codesimplemented by the controlling unit 905 according to the seventhembodiment. First, at STEP3800, the code combination creating unit 11defines the number of combinations of channelization codes as Num, a setof combinations of all channelization codes as T, the smallest SF of alldata channels (E-DPDCHs) as sf, and a magnitude of the current overshootas D, and the code combination creating unit 11 initializes D to themaximum value sf/2 and stores in the memory 15. At STEP3801, the codecombination creating unit 11 sets Num=Num−1, initializes m to 1, selectsan arbitrary combination from T to define as C₁, deletes the combinationselected from T from the memory 15, and updates the memory 15. AtSTEP3802, the inter-chip phase variation calculating unit 12 obtains aphase variation θ_(m) from the (2m−1)th chip to the 2m-th chip in caseof assigning the combination C₁ to the channels and stores in the memory15. At STEP3803, it is set as m=m+1. At STEP3804, m>sf/2 is examined. Ifm>sf, STEP3805 is implemented. If not m=sf/2, the operation returns toSTEP3802. At STEP3805, the code combination determining unit 13 definesa parameter for obtaining a magnitude of overshoot for the combinationC₁ as D₁=sin²θ₁+sin²θ₂+ . . . +sin²θ_(sf/2) and stores in the memory 15.At STEP3806, the code combination determining unit 13 judges if theovershoot for C, is smaller than D. Namely, D₁<D is examined. If D₁<D,ST3807 is implemented. If not D₁<D, STEP3808 is implemented. AtSTEP3807, the code combination determining unit 13 replaces C withanother combination of the channelization codes which creates smallerovershoot. That is, it is set as C=C₁ and D=D₁, and stores in the memory15. At STEP3808, if Num>0, the operation returns to STEP3801. If Num≦0,STEP3809 is implemented. At STEP3809, the code assignment instructingunit 14 defines C stored in the memory 15 as an optimal combination, andthe code assignment instructing unit 14 assigns the channelization codesto each data channel based on this. The code assignment instructing unit14 notifies the channelization code generator 904 of the assignment ofchannelization codes.

In the present embodiment, overshoot for all combination ofchannelization codes for the data channel are obtained and from thatresult, a combination of the channelization codes which creates thesmallest overshoot is selected. By doing this, a combination of thechannelization codes which creates small overshoot can be automaticallyobtained by calculation even if the smallest SF of the data channels isother than 2 or 4.

Embodiment 8

Configuration of a communication apparatus according to the presentembodiment and a controlling unit provided at the communicationapparatus are the same as ones of the second embodiment shown in FIG. 9.

In the following explanation, another way is explained to automaticallyassign the channelization codes based on a gain factor of each datachannel instead of obtaining the optimal assignment by calculation likethe seventh embodiment. By doing this, it is possible to obtain the sameeffect with a smaller H/W (hardware) than the seventh embodiment. As hasbeen discussed using FIG. 38, the phase variations among plural chipsare respectively calculated for combinations of the channelizationcodes, and a combination of the channelization codes, with which a sumof overshoots created by the phase variations among plural chips issmall, is obtained by calculation according to the seventh embodiment.In the sixth embodiment, more concretely, to obtain a combination of thechannelization codes of which a sum of overshoots is small, acombination of the channelization codes, with which the phase variationbetween the first and second chips is close to 0 degrees or 180 degrees,is obtained. However, in fact at a chip level, since spreading is doneby the channelization codes and the calculation result should be storedin H/W, a H/W scale becomes larger in proportion to the number ofcombinations of the channelization codes. Therefore, instead ofobtaining the combination of channelization codes by calculation,another way is explained, in which the phase variation from anodd-numbered chip to an even-numbered chip is made close to 0 degrees or180 degrees as much as possible and far from 90 degrees as much aspossible by assigning the channelization codes to channels from achannel of which the degree of determining the phase variation is high.

First, a transport block size is explained. A transport block size meansa size of data transmitted by the terminal. When data to be transmittedis input to a transmission buffer of the terminal, the input data isdivided into appropriate sizes according to a unit of transmission time.This data which has been divided into appropriate sizes is referred toas a transport block, and its size is called as a transport block size.

Next, the number of data channels for transmission and determination ofSF will be discussed. Once the transport block size is determined, thenumber of data channels and a spreading factor SF is determined based onalgorithm defined in, for example, 3GPP specification document (TS25.212§ 4.8.4.1). When SF is determined, a gain factor is determined. A gainfactor is a weighing factor to be multiplied to each data channel (by aunit of symbol) before multiplexing (before multiplication of thechannelization codes). Since as the data amount is large, the powernecessary for reception becomes large, a larger gain factor is assignedto the data channel. Because of this, the gain factor of the datachannel having larger data amount (smaller SF) becomes larger than thatof the data channel having smaller data amount (larger SF). For example,the data channel with SF=2 requires twice as much power as the datachannel with SF=4 since the data channel with SF=2 transmits twice asmuch data as the data channel with SF=4. In order to double the power,the amplitude should be multiplied by √{square root over (2)}. Since thegain factor is a factor to be multiplied to the amplitude, the gainfactor of the data channel with SF=2 becomes √{square root over (2)}times as large as the gain factor of the data channel with SF=4.

It will be explained that channelization codes (I/Q axis) to be assignedto E-DPDCHs are also determined based on SF, the number of datachannels, and the data amount. In this embodiment, channelization codesC_(SF,k) of which the code number k is 0≦k≦(SF/2−1) is assigned to datachannels from the data channel having a large gain factor for both I andQ axes. Or channelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1) is assigned. When the operation is explained using acode tree shown in FIG. 41 that will be discussed later, if SF is 2,either of C_(2,0) or C_(2,1) is assigned to a data channel from the datachannel having a large gain factor; if SF is 4, both (or either) ofC_(2,0) and C_(2,1) or both (or either) of C_(4,0) and C_(4,1) areassigned to data channels from the data channel having a large gainfactor. Hereinafter, for convenience of the explanation, in the codetree, branches of which the code number k is 0≦k≦(SF/2−1) (in case ofSF=4, branches having C_(4,0) and C₄) are called “the upper side of codetree”, and branches of which the code number k is (SF/2)≦k≦(SF−1) (incase of SF=4, branches having C_(4,2) and C_(4,3)) are called “the lowerside of code tree”. Namely, in this embodiment, for both I and Q axes,by assigning any of channelization codes located at the upper side (thelower side) of the code tree to the data channel having a large gainfactor, and assigning a channelization code located at the lower side(the upper side) of the code tree to the data channel having a smallgain factor, the overshoot can be reduced.

When it cannot be obtained by the magnitudes of the gain factors (forexample, the values of gain factors are the same), the channelizationcodes are assigned to data channels from the data channel having largedata amount, since it is considered that transmission power of a channelhaving larger data amount is larger. Since a data channel having a smallSF is considered to have larger data amount than a data channel having alarge SF, the data is assigned to data channels from the data channelhaving a small SF. Because of this, a terminal determines channelizationcodes to be assigned to the data channels based on SF, the number ofdata channels, and the data amount for each data channel at both I and Qaxes.

A definition of a summation of gain factors will be explained. Thesummation of gain factors means, at a chip before a transition or afterthe transition, gain factors of the data channels, to which thechannelization codes are assigned, summed up at each of the I and Qaxes. β₁ through β₈ show summations of the gain factors and are definedas follows:

β₁=a summation of gain factors of which a transition from the first chipto the second chip at the I axis side is (1,1) (a summation of gainfactors of data channels, to which channelization codes that make atransition from the first chip to the second chip (1,1) are assigned andof which symbol data is 1)β₂=a summation of gain factors of which a transition from the first chipto the second chip at the I axis side is (−1,−1) (a summation of gainfactors of data channels, to which channelization codes that make atransition from the first chip to the second chip (1,1) are assigned andof which symbol data is −1)β₃=a summation of gain factors of which a transition from the first chipto the second chip at the Q axis side is (1,1) (a summation of gainfactors of data channels, to which channelization codes that make atransition from the first chip to the second chip (1,1) are assigned andof which symbol data is 1)β₄=a summation of gain factors of which a transition from the first chipto the second chip at the Q axis side is (−1,−1) (a summation of gainfactors of data channels, to which channelization codes that make atransition from the first chip to the second chip (1,1) are assigned andof which symbol data is −1)β₅=a summation of gain factors of which a transition from the first chipto the second chip at the I axis side is (1,−1) (a summation of gainfactors of data channels, to which channelization codes that make atransition from the first chip to the second chip (1,−1) are assignedand of which symbol data is 1)β₆=a summation of gain factors of which a transition from the first chipto the second chip at the I axis side is (−1,1) (a summation of gainfactors of data channels, to which channelization codes that make atransition from the first chip to the second chip (1,−1) are assignedand of which symbol data is −1)β₇=a summation of gain factors of which a transition from the first chipto the second chip at the Q axis side is (1,−1) (a summation of gainfactors of data channels, to which channelization codes that make atransition from the first chip to the second chip (1,−1) are assignedand of which symbol data is 1)β₈=a summation of gain factors of which a transition from the first chipto the second chip at the Q axis side is (−1,1) (a summation of gainfactors of data channels, to which channelization codes that make atransition from the first chip to the second chip (1,−1) are assignedand of which symbol data is −1)

When a transition from an odd-numbered chip to an even-numbered chip is(1,1) or (−1,−1), namely, the phase variation is 0 degrees, the codenumber k of the channelization codes C_(SF,k) is 0≦k≦(SF/2−1), and whena transition from an odd-numbered chip to an even-numbered chip is(1,−1) or (−1, 1), namely, the phase variation is 180 degrees, the codenumber k of the channelization codes C_(SF,k) is (SF/2)≦k≦(SF−1). Thatis, each of β₁ through β₄ is a summation of gain factors for thechannelization codes C_(SF,k) of which the code number k is0≦k≦(SF/2−1), and each of β₅ through β₈ is a summation of gain factorsfor the channelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1).

It will be explained that a summation of gain factors is determined whenchannelization codes and gain factors are determined. When the smallestSF is 2, only transitions of the first chip and the second chip shouldbe considered, since after the third chip, symbols output from the datachannel with SF=2 are different from the symbol of the first chip. Iflimited to a combination between two chips, a combination of thechannelization codes varies only two ways of (1,1) and (1,−1);combinations of chip transitions are four ways of (1,1), (−1,−1),(1,−1), and (1,−1), considering the symbol data. Therefore, if thechannelization code is determined, a combination of the chip transitionsis determined for each data channel based on the symbol data.Accordingly, a summation of gain factors β₁ through β₈ can be obtainedby adding the gain factors assigned to each data channel for eachcombination of the transitions of the same chip at each of I/Q axes.

It will be explained that a chip transition can be determined ifsummations of gain factors are determined. The magnitude of overshootcan be obtained by the chip transition. Accordingly, among the samesymbols, it is preferable to set the phase variation to 0 degrees or 180degrees as much as possible. The reason of this will be discussed later.A signal constellation can be represented like the following equations(1) and (2) regardless of channels, gain factors, whether symbol data is1 or (−1), and the number of multiplexing:before transition (I,Q)=(β₁−β₂+β₅−β₆, β₃−β₄+β₇−β₈)  (1)after transition (I,Q)=(β₁−β₂−β₅+β₆, β₃−β₄−β₇+β₈)  (2)

As shown in the above equations (1) and (2), the signal constellationsbefore and after the transition can be expressed by using summations ofgain factors, so that the chip transition can be determined if thesummations of gain factors are determined.

It will be explained that the summation of gain factors for thechannelization C_(SF,k) of which the code number k is 0≦k≦(SF/2−1) (β₁through β₄ in the above equations (1), (2)) does not determine the chiptransition, but the summation of gain factors for the channelizationcodes C_(SF,k) of which the code number k is (SF/2)≦k≦(SF−1) (β₅ throughβ₈ in the above equations (1), (2)) does affects the chip transition.When β₅ through β₈ are 0, the above equations (1) and (2) can beexpressed as the following equations (3) and (4):before transition (I,Q)=(β₁−β₂, β₃−β₄)  (3)after transition (I,Q)=(β₁−β₂, β₃−β₄)  (4)It is found that the signal constellations before/after transition arethe same when only the channelization codes C_(SF,k) of which the codenumber k is 0≦k≦(SF/2−1) are used, so that the phase variation from thefirst chip to the second chip is 0 degrees. This is because β₁ throughβ₄ in the above equations (3) and (4) show a case in which the phasevariation from the first chip to the second chip is 0 degrees, whichmeans these values do not determine the chip transition. As for featuresof the equations (3) and (4), since the part of β₅ through β₈ includesdifferent signs, they do not match between before and after thetransition. Accordingly, the values of β₅ through β₈ affect the chiptransition.

The patent document 1 which has been discussed discloses that when thechannelization codes C_(SF,k) of which the code number k is 0≦k≦(SF/2−1)is assigned to all data channels, the phase variation becomes 0 degrees,which reduces the overshoot. The patent document 1, however, does notdisclose assignment of the channelization codes when the number of datachannels is large, for example, the number of data channels is largerthan the number of channels to which the channelization codes C_(SF,k)of which the code number k is 0≦k≦(SF/2−1) can be assigned. Further, itdoes not disclose assignment of the channelization codes to datachannels of which the gain factors are different. Therefore, anothermethod will be explained for assigning the channelization codes when thenumber of data channels is large, and thus the channelization codesC_(SF,k) of which the code number k is 0≦k≦(SF/2−1) cannot be assignedto all data channels. β₁ through β₄ which are features of the equations(3) and (4) do not determine the chip transition, but express how farthe points before/after the transition are from a point of origin, andβ₅ through β₈ affect the chip transition. Among transitions of the samechips, the phase variation becomes small if one is far from the point oforigin. Because of this, the overshoot can be reduced when thechannelization codes are assigned so that β₁ through β₄ should be madelarge and β₅ through β₈ should be made small. Accordingly, it isconsidered that the overshoot can be reduced by assigning thechannelization codes C_(SF,k) of which the code number k is 0≦k≦(SF/2−1)to data channels having larger gain factors and then assigning thechannelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1) to the remaining data channels.

A concrete example will be explained, in which the summation of gainfactors for the channelization codes C_(SF,k) of which the code number kis 0≦k≦(SF/2−1) (β₁ through β₄ in the above equations (1), (2)) does notdetermine the chip transition, but the summation of gain factors for thechannelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1) (β₅ through β₈ in the above equations (1), (2)) affectsthe chip transition. As a condition of the concrete example, it isassumed that there are one data channel with SF=2 (the gain factor iscorrected by being multiplied by √{square root over (2)}) and one datachannel with SF=4(the gain factor is 1) at the I and Q axes,respectively. Namely, it is when there are two channels with SF=2 andtwo channels with SF=4. It is assumed that there are one data channelwith SF=2 and one data channel with SF=4 at the I and Q axes,respectively. Here, a clash of the channelization codes with anotherchannel such as a control channel is not considered. C_(2,0) is assignedto the data channel with SF=2 of which the gain factor is large, thatis, the data channel with SF=2, to which the gain factor valuemultiplied by √{square root over (2)} is multiplied, and C_(4,2) (orC_(4,3)) is assigned to the data channel with SF=4 of which the gainfactor is small. It is assumed that a symbol of the data channel withSF=2 at the I axis is 1, that a symbol of the data channel with SF=2 atthe Q axis is −1, that a symbol of the data channel with SF=4 at the Iaxis is 1, and that a symbol of the data channel with SF=4 at the Q axisis −1. In such a case, when summations of gain factors are obtained,β₁=√{square root over (2)}, β₂=0, β₃=0, β₄=√{square root over (2)},β₅=1, β₆=0, β₇=0, and β₈=1. By substituting these values to theequations (1) and (2), signal constellations before/after the transitionare obtained as follows:before transition (I, Q)=(√{square root over (2)}+1, −√{square root over(2)}−1)  (5)after transition (I, Q)=(√{square root over (2)}−1, −√{square root over(2)}+1)  (6)

In this case, the channelization codes C_(SF,k) of which the code numberk is 0≦k≦(SF/2−1) are assigned to data channels from the data channel ofwhich the gain factor is large.

In the equations (5) and (6), √{square root over (2)} shows a summation(β₁ through β4) of the gain factors of which values are the same in thesignal constellations before/after the transition, and 1 shows asummation (β₅ through β₈) of the gain factors of which positive ornegative signs are opposite in the signal constellations before/afterthe transition. Accordingly, while the summation (β₁ through β₄) of thegain factors of which values are the same in the signal constellationsshown by the equations (5) and (6) before/after the transition is√{square root over (2)}, the summation (β₅ through β₈) of the gainfactors of which positive or negative signs are opposite in the signalconstellations before/after the transition is 1, so that the summation(β₅ through β₈) of the gain factors is always smaller than the summation(β₁ through β₄) of the gain factors at both the I and Q axes. Because ofthis, in the signal constellations before/after the transition, thesummation (β₁ through β₄) of the gain factors always determine thepositive or negative signs in the signal constellations before/after thetransition. Therefore, in the equation (1) before the transition and theequation (2) after the transition, the summation (β₁ through β₄) of thegain factors at the I axis (β₁-β₂) and the Q axis (β₃- β₄) are the sameform, so that the summation (β₁ through β₄) of gain factors does notreverse the positive or negative signs of the components of the I and Qaxes before/after the chip transition.

A concrete example will be explained, in which the overshoot can bereduced if the summation of gain factors for the channelization codesC_(SF,k) of which the code number k is 0≦k≦(SF/2−1) (β₁ through β₄ inthe above equations (1), (2)) is made large, and the summation of gainfactors for the channelization codes C_(SF,k) of which the code number kis (SF/2)≦k≦(SF−1) (β₅ through β₈ in the above equations (1), (2)) ismade small. When (β₁−β₂+β₅−β₆) which is a component of the I axis beforethe chip transition is compared with (β₁−β₂−γ₅+β₆) which is a componentof the I axis after the chip transition, the components of the I axisare both positive, and the positive or negative signs are not reversed.When the components of the Q axis are compared as well, the componentsof the Q axis are both negative, and the positive or negative signs arenot reversed. Therefore, the phase variation is very small, since thepositive or negative signs are not reversed at each of the I/Q axes. Inthe case when a symbol is changed, the case is equivalent to that of thecorresponding summation (β₁ through β₈) of gain factors being multipliedby (−1). Nevertheless, it is understood that the absolute values are notchanged if a symbol of any data channel is changed, and thus thepositive or negative sign is not reversed at each of the I/Q axes.

It will be explained that the summation of gain factors for thechannelization C_(SF,k) of which the code number k is (SF/2)≦k≦(SF−1)(β₅ through β₈ in the above equations (1), (2)) affects the chiptransition to reverse the positive or negative signs, and the summationof gain factors for the channelization codes C_(SF,k) of which the codenumber k is 0≦k≦(SF/2−1) (β₁ through β₄ in the above equations (1), (2))does not affect the chip transition. When β₁ through β₄ are 0 in theabove equations (1) and (2), the following can be said:before transition (I,Q)=(β₅−β₆,β₇−β₈)  (7)after transition (I,Q)=(−β₅+β₆,−β₇+β₈)  (8)

When only the channelization codes C_(SF,k) of which the code number kis 0≦k≦(SF/2−1) are used like the equations (7) and (8), the positive ornegative signs of the signal constellations are reversed before/afterthe transition at both I and Q axes as shown in the equations (7) and(8), so that the equations are symmetric about the origin. Accordingly,the phase variation from the first chip to the second chip becomes 180degrees. This is because β₁ through β₄ in the above equations (1), (2)show cases in which the phase variation from the first chip to thesecond chip is 0 degrees, and thus these values do not determine thechip transition. Upon considering features of the equations (1) and (2),the same signs are appended to each part of β₁ through β₄ so that theymatch before/after the chip transition. Therefore, the signalconstellations are moved to the same direction and at the same amountbefore/after the chip transition based on the values of β₁ through β₄,and their form becomes less symmetric about the point of origin by theamount, so that the phase variation becomes small.

If the channelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1) are assigned to all data channels, the phase variationbecomes 180 degrees, which leads to small overshoot. In theabove-described ways, however, there may be a case no channelizationcodes can be assigned when the number of data channels is large. Anothermethod will be explained for assigning the channelization codes when thenumber of data channels is greater than, for example, the number towhich the channelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1) can be assigned. β₅ through β₈ which are features in theabove equations (1), (2) show cases in which the phase variation becomes180 degrees, so that β₁ through β₄ which do not determine the chiptransition have an effect to reduce the phase variation. Therefore, whenthe channelization codes are assigned so as to make β₅ through β₈ largeand β₁ through β₄ small, the phase variation becomes close to 180degrees, and thus the overshoot is small. Then, it is considered thatthe overshoot can be reduced if the channelization codes C_(SF,k) ofwhich the code number k is (SF/2)≦k≦(SF−1) are assigned to data channelsfrom the data channel of which the gain factor is large and thechannelization codes C_(SF,k) of which the code number k is 0≦k≦(SF/2−1)are assigned to the remaining data channels.

A concrete example will be explained, in which a summation of gainfactors for the channelization codes C_(SF,k) of which the code number kis (SF/2)≦k≦(SF−1) (β₅ through β₈ in the above equations (1), (2)) doesnot determine a chip transition, but the summation of gain factors forthe channelization codes C_(SF,k) of which the code number k is0≦k≦(SF/2−1)(β₁ through β₄ in the above equations (1), (2)) affects thechip transition. As a condition of the concrete example, it is assumedthat there are one data channel with SF=2 (the gain factor is √{squareroot over (2)}) and one data channel with SF=4 (the gain factor is 1) ateach of the I and Q axes. Namely, it is when there are two channels withSF=2 and two channels with SF=4. It is assumed that there are one datachannel with SF=2 and one data channel with SF=4 at each of the I and Qaxes. C_(2,1) is assigned to the data channel with SF=2 of which thegain factor is large, and C_(4,0) (or C_(4,1)) is assigned to the datachannel with SF=4 of which the gain factor is small. In case that asymbol of the data channel with SF=2 at the I axis is 1, a symbol of thedata channel with SF=2 at the Q axis is −1, a symbol of the data channelwith SF=4 at the I axis is 1, and a symbol of the data channel with SF=4at the Q axis is −1, when a summation of gain factors is obtained, β₁=1,β₂=0, β₃=0, β₄=1, β₅=√{square root over (2)}, β₆=0, β₇=0, andβ₈=√{square root over (2)}. By substituting these values to theequations (1) and (2), signal constellations before/after the transitionare obtained as follows:before transition (I, Q)=(1+√{square root over (2)}, −1−√{square rootover (2)})  (9)after transition (I, Q)=(1−√{square root over (2)}, −1+√{square rootover (2)})  (10)

In this case, the channelization codes C_(SF,k) of which the code numberk is (SF/2)≦k≦(SF−1) are assigned to data channels from the data channelof which the gain factor is large.

In the equations (9) and (10), √{square root over (2)} shows a summation(β₅ through β₈) of the gain factors of which positive or negative signsare opposite in the signal constellations before/after the transition,and 1 shows a summation (β₁ through β₄) of the gain factors of whichvalues are the same in the signal constellations before/after thetransition. Accordingly, while the summation (β₅ through β₈) of the gainfactors of which positive or negative signs are opposite in the signalconstellations shown by the equations (9) and (10) before/after thetransition is √{square root over (2)}, the summation (β₁ through β₄) ofthe gain factors of which values are the same in the signalconstellations before/after the transition is 1, so that the summation(β₁ through β₄) of the gain factors is always smaller than the summation(β₅ through β₈) of the gain factors at both the I and Q axes. Because ofthis, in the signal constellations before/after the transition, thesummation (β₅ through β₈) of the gain factors always determine thepositive or negative signs in the signal constellations before/after thetransition. Therefore, in the equation (1) before the transition and theequation (2) after the transition, positive or negative signs of thesummation (β₅ through β₈) of the gain factors are opposite such as atthe I axis (β₅−β₆) and the Q axis (β₇−β₈) in the equation (1), while theI axis (β₆−β₅) and the Q axis (β₈−β₇) in the equation (2), so that thesummation (β₅ through β₈) of the gain factors always reverse thepositive or negative signs of the components of the I and the Q axesbefore/after the chip transition.

A concrete example will be explained, in which the overshoot can bereduced if a summation of gain factors for the channelization codesC_(SF,k) of which the code number k is (SF/2)≦k≦(SF−1)(β₅ through β₈ inthe above equations (1), (2)) is made large, and a summation of gainfactors for the channelization codes C_(SF,k) of which the code number kis 0≦k≦(SF/2−1)(β₁ through β₄ in the above equations (1), (2)) is madesmall. When (β₁−β₂+β₅−β₆) which is a component of the I axis before thetransition is compared with (β₁−β₂−β₅+β₆) which is a component of the Iaxis after the transition, the component of the I axis is positivebefore the chip transition and negative after the chip transition, andthe positive or negative sign is reversed. When the components of the Qaxis are compared as well, the component of the Q axis before the chiptransition is negative and positive after the chip transition, and thepositive or negative sign is reversed. Therefore, the phase variation isvery large, since the positive or negative signs are always reversed ateach of the I/Q axes. In the case when a symbol is changed, the case isequivalent to that of the corresponding summation (β₁ through β₈) of thegain factors being multiplied by (−1). Nevertheless, it is understoodthat the positive or negative signs are always reversed at each of theI/Q axes if a symbol of any data channel is changed.

It will be explained that when summations of gain factors aredetermined, a weighing factor for a chip of the I/Q axes is determined.A weighing factor for a chip of the I/Q axes means components(components of horizontal and vertical axes when a vector is decomposedinto orthogonal axes) of the I/Q axes of the chip right before the HPSKmodulation before the transition or after the transition. Namely, aweighing factor is a factor multiplied to the I/Q plane axes (by chipunit) after the multiplex (after multiplication of channelization codesto each of data channels). As shown in the equations (1) and (2), theweighing factor for the chip of the I/Q axes is defined by the summationof gain factors β₁ through β₈, so that the weighing factor isautomatically determined if the summation of gain factors is determined(since each of the data channels is multiplexed and arranged into onesignal space, a location where a certain chip of one data channel isarranged depends on each symbol data of the data channel and the gainfactor multiplied to the symbol data).

It will be explained that a phase variation (angle) is determined if aweighing factor for the chip of the I,Q axes is determined. The equation(1) shows a weighing factor for the chip of the I/Q axes before thetransition, and the equation (2) shows a weighing factor for the chip ofthe I/Q axes after the transition. Since each weighing factor for thechip of I/Q axes shows a component of the I/Q axes of a constellation,constellations before the transition and after the transition can beobtained from the equations (1) and (2), and the transition of chip canbe obtained by calculating a difference of the two equations.

It will be explained that when all of the channelization codes C_(SF,k)of which the code number k is (SF/2)≦k≦(SF−1) are assigned to channelshaving larger gain factors, and the channelization codes C_(SF,k) ofwhich the code number k is 0≦k≦(SF/2−1) are assigned to channels havingsmaller gain factors, the phase variation becomes close to 0 degrees or180 degrees. In order to make the overshoot small, it is desired not tomix C_(2,0), C_(4,0), C_(4,1) with C_(2,1), C_(4,2), C_(4,3) as much aspossible. As the phase variation θ is determined by β₁ through β₈ whichare the summations of gain factors, C_(2,0), C_(4,0), C_(4,1) orC_(2,1), C_(4,2), C_(4,3) is assigned to channels from the channel whichhas a higher degree of determining the phase variation θ. The phasevariation θ is determined by the chip transition, namely, by theweighing factor for the chip of the I/Q axes. To have a higher degree ofdetermining the phase variation θ means that the weighing factor for thechip of the I/Q axes is large, namely, the gain factor or data amount islarge, and SF is small. Therefore, when C_(2,0), C_(4,0), C_(4,1)(C_(2,1), C_(4,2), C_(4,3)) are assigned to channels from the channelwhich has a higher degree of determining the phase variation θ, thephase variation θ becomes 0 degrees or 180 degrees, and the overshootcan be reduced. Size of the effect given to β₁ through β₈ can beobtained by the gain factor, so that, as well as the second embodiment,it is preferable to assign C_(2,0), C_(4,0), C_(4,1) (C_(2,1), C_(4,2),C_(4,3)) to channels from a channel having a larger gain factor as muchas possible.

A case will be explained, in which only one data channel having a largegain factor uses all of the channelization codes C_(SF,k) of which thecode number k is 0≦k≦(SF/2−1) in both I/Q axes. In such a case, thechannelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1) are assigned to a channel having a small gain factor,and the channelization codes C_(SF,k) of which the code number k is0≦k≦(SF/2−1) are assigned to a channel having a large gain factor, andconsequently, the overshoot becomes small. In either of the I/Q axes,when only one data channel having a large gain factor uses all of thechannelization codes C_(SF,k) of which the code number k is0≦k≦(SF/2−1), if the channelization codes C_(SF,k) of which the codenumber k is 0≦k≦(SF/2−1) are assigned to the channel having a large gainfactor, it is always determined that the channelization codes C_(SF,k)of which the code number k is (SF/2)≦k≦(SF−1) are assigned to theremaining data channels in the same axes. This means that it is alwaysdetermined that the channelization codes C_(SF,k) of which the codenumber k is 0≦k≦(SF/2−1) are assigned to the data channel of which thegain factor is large if a channelization code C_(SF,k) of which the codenumber k is (SF/2)≦k≦(SF−1) is assigned to one of data channels of whichthe gain factors are not large. It is similarly true in case that thechannelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1) are assigned to a data channel of which the gain factoris large. In such a case, assigning the channelization codes C_(SF,k) ofwhich the code number k is 0≦k≦(SF/2−1) from a data channel of which thegain factor is large is equivalent to assigning the code number k is(SF/2)≦k≦(SF−1) from a data channel of which the gain factor is small.Because of this, when only one data channel having a large gain factoruses all the channelization codes of the upper side, the channelizationcodes can be assigned from a data channel having a small gain factor.For example, when there are one data channel with SF=2 and one datachannel with SF=4 in the I/Q axes, respectively, the data channel withSF=2 uses all codes of one side, so that assignment can be carried outfrom the data channel with SF=2 or from the data channel with SF=4.

It will be explained that the phase variation approaches to 90 degreesif one having a large gain factor and one having a small gain factor arealternately assigned. In case that the channelization codes are assignedalternately to one having a large gain factor and one having a smallgain factor, when there are, for example, two data channels with SF=2and two data channels with SF=4 (one in each of I/Q axes), if C_(2,0) isassigned to the data channel with SF=2 at the I side, C_(4,1) isassigned to the data channel with SF=4 at the Q side, C_(4,2) isassigned to the data channel with SF=4 at the I side, and C_(2,1) isassigned to the data channel with SF=2 at the Q side, the phasevariation is close to 90 degrees.

FIG. 39 is a flowchart showing assignment of the channelization codesbased on the size of SF when there is no HS-DPCCH. At STEP3900, the codeassigning unit by gain factor 21 assigns C_(2,1) to data channels(E-DPDCHs) with SF=2 at the I and Q sides, respectively and stores inthe memory 15. By assigning the channelization codes to the datachannels of which SF is small beforehand, it is possible to reduce theovershoot as well as the first to seventh embodiments that have beendiscussed above. In the following STEP3901 through STEP3905, a way willbe explained in which unused channelization codes are assignedefficiently to the data channels. At STEP3901, the remaining codeassigning unit 22 assigns C_(4,1) to a data channel (E-DPDCH) with SF=4at the Q side and stores in the memory 15. At STEP3902, the remainingcode assigning unit 22 judges if a DPDCH is used. If a DPDCH is used,STEP3905 is implemented. On the other hand, if a DPDCH is not used,STEP3903 is implemented. At STEP3903, the remaining code assigning unit22 judges if an E-DPCCH is at the I side. If an E-DPCCH is at the Iside, STEP3905 is implemented. If an E-DPCCH is not at the I side,STEP3904 is implemented. At STEP3904, the remaining code assigning unit22 assigns C_(4,1) or C_(4,0) to the data channel (E-DPDCH) with SF=4 atthe I side and stores in the memory 15. At STEP3905, the remaining codeassigning unit 22 assigns C_(4,0) to the data channel (E-DPDCH) withSF=4 at the I side and stores in the memory 15.

As for the channelization code for an E-DPCCH, it is preferable to usethe channelization code C_(256,k) (64≦k≦127) so that one data channel(E-DPDCH) with SF=2 and one data channel (E-DPDCH) with SF=4 should besuperimposed at the I side. The reason of this will be discussed later.However, this assumption is applied to a case when there are somepossibilities to use a DPDCH while an E-DPDCH is used, and if a DPDCH isnot used while an E-DPDCH is used, k can be any value as long as0≦k≦127. In this case, at STEP3905, if the code number k for an E-DPCCHis 0≦k≦63, C_(4,1) is assigned to the data channel (E-DPDCH), and if thecode number k for the E-DPCCH is 64≦k≦127, C_(4,0) is assigned to thedata channel (E-DPDCH). This flowchart does not define an order of timeto assign the channelization codes, but defines an order of priority toassign. For example, a timing when the controlling unit 905 sets thechannelization codes can be the same.

FIG. 40 shows an example of assignment of the channelization codes basedon the magnitude of SF when there is no HS-DPCCH. If DPDCH₁ for theRelease 5 (Rel5) is assumed to transmit at 64 kbps, C_(16,4) isassigned. C_(256,2) is assigned to an E-DPCCH. First, the channelizationcode C_(2,1) is assigned to E-DPDCH, and E-DPDCH₂ that are the datachannels with SF=2. Next, the channelization code C_(4,1) is assigned toE-DPDCH₄ that is the data channel with SF=4 at the Q side. Then, thechannelization code C_(4,0) is assigned to E-DPDCH₃ that is the datachannel with SF=4 at the I side, since the I side includes a DPDCH.

FIG. 41 shows a code tree of the channelization codes at the I axis. Thecode tree at the I axis 4100 is a code tree of the channelization codesat the I axis that has been used for the explanation of the aboveseventh embodiment. In FIG. 41, 4101 a through 4101 n showchannelization codes for each SF (SF=2, SF=4, and SF=8). A bold line4102 shows that channelization codes 4101 a(C_(2,0)), 4101 d(C_(4,1)),4101 i(C_(8,2)) are used for a DPDCH. The channelization codes 4101a(C_(2,0)), 4101 d(C_(4,1)), 4101 i(C_(8,2)) that have been alreadyassigned to the DPDCH cannot be assigned to another channel. In casethat the I axis is provided with one data channel with SF=2 and one datachannel with SF=4, if the number of the DPDCH is changed, a base stationof the Release 5 becomes incompatible, and thus soft handover becomesdifficult. Accordingly, the channelization codes that are used for theDPDCH cannot be assigned. Therefore, it is preferable to first assignthe channelization code 4101 b(C_(2,1)) to the data channel with SF=2,and then assign the channelization code 4101 c(C_(4,0)) to the datachannel with SF=4. Accordingly, when an E-DPCCH is used at the I side,if SF=256, it is desired to use the channelization code C_(256,k)(64≦k≦127).

FIG. 42 shows a code tree of the channelization codes of the Q axis. InFIG. 42, 4201 a through 4201 n show channelization codes for each SF(SF=2, SF=4, and SF=8). A bold line 4202 shows that channelization codes4201 a(C_(2,0)), 4201 c(C_(4,0)), 4201 g(C_(8,0)) are used for a DPDCH.A bold line 4203 shows that channelization codes 4201 a(C_(2,0)), 4201d(C_(4,1)), 4201 i(C_(8,2)) are used for an HS-DPCCH. If the I axis isprovided with one data channel with SF=2 and one data channel with SF=4,since the channelization codes being used by the DPCCH that is alwaysemployed for communication cannot be assigned, it is preferable to firstassign the channelization code 4201 b(C_(2,1)) to the data channel withSF=2, and then assign the channelization code 4201 d(C_(4,1)) to thedata channel with SF=4. However, since the channelization code 4201d(C_(4,1)) is being used by the HS-DPCCH, this assignment causes toclash with the HS-DPCCH. Soft-handover does not occur in the HS-DPCCH,so that it is possible to keep compatibility with the conventional basestation even if the code number is changed. Therefore, if the Q axis isprovided with one data channel with SF=2 and one data channel with SF=4,assignment of the codes to the HS-DPCCH is set to, for example,C_(256,1) or C_(256,32) of the channelization code C_(256,k) (1≦k≦63) toavoid the clash with the data channel (E-DPDCH). However, when thenumber of data channels (E-DPDCHs) has been already limited to thenumber that does not cause to clash with the HS-DPCCH, the assignment ofthe codes to the HS-DPCCH can be set in the same way with the Release 5.Further, when an E-DPCCH is used at the Q side, if SF=256, it ispreferable to use the channelization code C_(256,k) (1≦k≦63) that doesnot cause the clash with the HS-DPCCH.

FIG. 43 is a flowchart showing assignment of the channelization codesbased on the magnitude of SF when there is an HS-DPCCH. At STEP4300, thecontrolling unit 905 sets the C_(256,k) (1≦k≦63) as assignment for anHS-DPCCH. For example, it is set to C_(256,1) or C_(256,32). However,when the number of data channels (E-DPDCHs) is limited to no more thanthree from the first, the assignment of the codes to the HS-DPCCH can bethe same with the Release 5. In such a case, STEP4300 can be omitted. AtSTEP4301, the code assigning unit by gain factor 21 assigns C_(2,1) tothe data channels (E-DPDCHs) with SF=2 at the I and Q sides,respectively and stores in the memory 15. And then, at STEP4302, theremaining code assigning unit 22 assigns C_(4,0) to the data channelswith SF=4 at the I side and stores in the memory 15. This is because theassignment of C_(4,1) causes the clash with the DPDCH. Further, atSTEP4303, the remaining code assigning unit 22 assigns C_(4,1) to thedata channels (E-DPDCHs) with SF=4 at the Q side and stores in thememory 15. This is because the assignment of C_(4,0) causes the clashwith the DPCCH. Since both the DPCCH and the DPDCH are channelsspecified in the Release 99 (R99), backward compatibility will be lostif the channelization code numbers are changed, and thus soft-handovercannot be carried out. This flowchart does not define an order of timeto assign the channelization codes, but defines an order of priority forthe assignment. Timing for setting the channelization codes by thecontrolling unit 905 can be the same.

FIG. 44 is an example showing assignment of the channelization codesbased on the magnitude of SF when there is an HS-DPCCH. As the HS-DPCCHis used, the assignment of the codes for the HS-DPCCH is set toC_(256,1). C_(16,4) is assigned to DPDCH₁ for the Release 5 if DPDCH₁transmits at 64 kbps. C_(256,2) is assigned to an E-DPCCH. First, thechannelization code C_(2,1) is assigned to E-DPDCH₁ and E-DPDCH₂ thatare the data channels with SF=2. Next, the channelization code C_(4,0)is assigned to E-DPDCH₃ that is the data channel with SF=4 at the Iside, since there is a DPDCH at the I side. Then, the channelizationcode C_(4,1) is assigned to E-DPDCH₄ that is the data channel with SF=4at the Q side.

The above discussed way will be generalized and considered.

Any channelization code can be developed and expressed by achannelization code for SF=2. FIG. 45 is a table showing a structure ofa channelization code. A channelization code for SF=2 means achannelization code for SF=2 that is the minimum SF. A channelizationcode for SF=sf shows a structure of the channelization code which is notfor SF=2. It is understood that one time development makes the codenumber k a quotient obtained by division with 2. Here, thechannelization code for SF=sf of which the code number is k is developedto SF=2. When the code number k is 0≦k≦(SF/2−1), a quotient obtained bydivision with SF/2 becomes 0, so that if the development is done toSF=2, the channelization code consists of C_(2,0) or −C_(2,0). Further,when the code number k is (SF/2)≦k≦(SF−1), a quotient obtained bydivision with SF/2 becomes 1, so that if the development is done toSF=2, the channelization code consists of C_(2,1) or −C_(2,1).

A case will be explained in which the channelization codes C_(SF,k) allof which the code number k is 0≦k≦(SF/2−1). In this case, for any valueof SF, a phase variation from an odd-numbered chip to an even-numberedchip always remains 0 degrees even if a gain factor is changed. Thiswill be verified by the following expressions. Only C_(2,0)=(1,1),−C_(2,0)=(−1,−1) are used for the channels of both I and Q sides. If thecase is limited to a transition from an odd-numbered chip to aneven-numbered chip of a certain part, the following expressions can beapplied regardless of kinds of channels, values of gain factors, and thenumber of multiplexing. In the following, β₁ through β₄ are realnumbers.I=β₁−β₂, β₁−β₂Q=β₃−β₄, β₃−β₄

As shown in the above, the phase variation of this part is 0 degrees.This can be verified in the same manner for all phase variations from anodd-numbered chip to an even-numbered chip, so that the phase variationfrom an odd-numbered chip to an even-numbered chip maintains 0 degrees.

Next, a case will be explained in which the channelization codesC_(SF,k) of which the code number k is (SF/2)≦k≦(SF−1). In this case,for any value of SF, a phase variation from an odd-numbered chip to aneven-numbered chip always remains 180 degrees even if a gain factor ischanged. Only C_(2,1)=(1,−1), −C_(2,1)=(−1,1) are used for the channelsof both I and Q sides. If the case is limited to a transition from anodd-numbered chip to an even-numbered chip of a certain part, thefollowing expressions can be applied regardless of kinds of channels,values of gain factors, and the number of multiplexing. In thefollowing, β₅ through β₈ are real numbers.I=β₅−β₆, −β₅+β₆Q=β₇−β₈, −β₇+β₈

As shown in the above, the phase variation of this part is 180 degrees.This can be verified in the same manner for all phase variations from anodd-numbered chip to an even-numbered chip, so that the phase variationfrom an odd-numbered chip to an even-numbered chip maintains 180degrees.

A case will be explained in which the channelization codes C_(SF,k) ofwhich the code number k is 0≦k≦(SF/2−1) and the channelization codesC_(SF,k) of which the code number k is (SF/2)≦k≦(SF−1) are mixed. Inthis case, as for a transition from an odd-numbered chip to aneven-numbered chip, only C_(2,0)=(1,1), −C_(2,0)=(−1,−1),C_(2,1)=(1,−1), −C_(2,1)=(−1,1) are used for the channels of both I andQ sides. If the case is limited to a transition from an odd-numberedchip to an even-numbered chip of a certain part, the followingexpressions can be applied regardless of kinds of channels, values ofgain factors, and the number of multiplexing. In the following, β₁through β₈ are real numbers.I=β ₁−β₂+β₅−β₆, β₁−β₂−β₅+β₆Q=β ₃−β₄+β₇−β₈, β₃−β₄−β₇+β₈

As shown in the above, the phase variation of this part does not become0 degrees or 180 degrees unless β₁ through β₄ are 0 or β₅ through β₈ are0. This can be verified in the same manner for all phase variations froman odd-numbered chip to an even-numbered chip, so that the phasevariations from an odd-numbered chip to an even-numbered chip cannot be0 degrees or 180 degrees when both of the channelization codes C_(SF,k)of which the code number k is 0≦k≦(SF/2−1) and the channelization codesC_(SF,k) of which the code number k is (SF/2)≦k≦(SF−1) are used.Therefore, it is preferable to use only the channelization codesC_(SF,k) of which the code number k is 0≦k≦(SF/2−1) or only thechannelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1).

Whatever SF is, the phase variation becomes close to 90 degrees if thechannelization codes C_(SF,k) of which the code number k is 0≦k≦(SF/2−1)and the channelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1) are mixed at the I side or the Q side. Accordingly, itis desired that the channelization codes C_(SF,k) of which the codenumber k is 0≦k≦(SF/2−1) and the channelization codes C_(SF,k) of whichthe code number k is (SF/2)≦k≦(SF−1) should not be mixed as much aspossible. For this, absolute values of β₁ through β₄ should be madelarge and absolute values of β₅ through β₈ should be made small, or theabsolute values of β₅ through β₈ should be made large and the absolutevalues of β₁ through β₄ should be made small. That is, at the I and Qaxes, β₁ through β₄ should be made large and β₅ through β₈ should bemade small by increasing a weighing factor for chips of the I/Q axis, towhich the channelization codes that make the chip transition (1,1) or(−1,−1) are assigned when the transition is limited to between twochips. Or, on the other hand, at the I and Q axes, β₅ through β₈ shouldbe made large and β₁ through β₄ should be made small by increasing aweighing factor for chips of the I/Q axis, to which the channelizationcodes that make a chip transition (1,−1) or (−1,1) are assigned when thetransition is limited to between two chips. This can be implemented bymaking channels (1,1) or (−1,−1) from a channel of which the weighingfactor for chips of the I/Q axis is large, namely, by assigning thechannelization codes C_(SF,k) of which the code number k is0≦k≦(SF/2−1). Or, on the other hand, it can be implemented by makingchannels (1,−1) or (−1,1) from a channel of which the weighing factorfor chips of the I/Q axis is large, namely, by assigning thechannelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1). Assigning the channelization codes to channels from achannel of which the weighing factor for chips of the I/Q axis is largeis equivalent to assigning the channelization codes to data channelsfrom a data channel in which an absolute value of the gainfactor/(β₁+β₂+ . . . +β₈) is large. Since the phase variation θ isdetermined by β₁ through β₈ that are summations of gain factors, it isequivalent to assigning the channelization codes C_(SF,k) of which thecode number k is 0≦k≦(SF/2−1) to channels from a channel which has ahigher degree to determine the phase variation θ, or is equivalent toassigning the channelization codes C_(SF,k) of which the code number kis (SF/2)≦k≦(SF−1) to channels from a channel which has a higher degreeto determine the phase variation θ. That is, when the channelizationcodes C_(SF,k) of which the code number k is 0≦k≦(SF/2−1) are assignedto channels from the channel which has a higher degree to determine thephase variation θ, or the channelization codes C_(SF,k) of which thecode number k is (SF/2)≦k≦(SF−1) are assigned to channels from thechannel which has a higher degree to determine the phase variation θ,the phase variation θ can be made close to 0 degrees or 180 degrees asmuch as possible, so that the overshoot can be reduced. Consequently,when the channelization codes C_(SF,k) of which the code number k is0≦k≦(SF/2−1) are assigned to channels from the channel which has ahigher degree to determine the phase variation θ, or C_(2,1), C_(4,2),and C_(4,3) are assigned to channels from the channel which has a higherdegree to determine the phase variation θ, the overshoot can be reduced.

Namely, as well as the second embodiment, it is effective to assign thechannelization codes C_(SF,k) of which the code number k is 0≦k≦(SF/2−1)to channels from the channel of which the gain factor is large or assignthe channelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1) to channels from the channel of which the gain factor islarge. Concretely, for example, when the channelization codes C_(SF,k)of which the code number k is 0≦k≦(SF/2−1) are assigned at the I axis,the channelization codes C_(SF,k) of which the code number k is0≦k≦(SF/2−1) are also assigned at the Q axis. On the other hand, whenthe channelization codes C_(SF,k) of which the code number k is(SF/2)≦k≦(SF−1) are assigned at the I axis, the channelization codesC_(SF,k) of which the code number k is (SF/2)≦k≦(SF−1) are also assignedat the Q axis. When the optimal assignment cannot be obtained based onthe magnitudes of the gain factors, it is considered that transmissionpower of a channel which carries larger data is larger, so that it ismore effective to assign the channelization codes to data channels fromthe data channel of which the data amount is large as well as the thirdembodiment. In another way, a channel of which SF is small is consideredto have larger data amount than a data channel of which SF is large, sothat it is more effective to assign the channelization codes to datachannels from a data channel of which SF is small.

FIGS. 46 and 47 are flowcharts showing assignment of the channelizationcodes when data channels having different SFs are multiplexed. AtSTEP4600, the controlling unit 905 defines, out of all channelizationcodes, a group of all channelization codes C_(SF,k) of which the codenumber k is 0≦k≦(SF/2−1) as a group A, and a group of all channelizationcodes C_(SF,k) of which the code number k is (SF/2)≦k≦(SF−1) as a groupB. At STEP4601, the controlling unit 905 judges if an HS-DPCCH is used.If it is used, STEP4602 is implemented. If an HS-DPCCH is not used,STEP4603 is implemented. At STEP4602, the controlling unit 905 setsassignment of the codes for an HS-DPCCH. When the number of datachannels is limited to the number which does not cause to clash with theHS-DPCCH from the first, the assignment of the codes for the HS-DPCCHcan be the same with the Release 5. In this case, STEP4601 and STEP4602can be omitted.

At STEP4603, the code assigning unit by gain factor 21 judges if it ispossible to assign to every data channel of the I and Q axes using onlychannelization codes of the group A without causing to clash with otherchannels. If it is possible to assign, STEP4604 is implemented. On theother hand, if it is not possible to assign, STEP4605 is implemented. AtSTEP4604, the code assigning unit by gain factor 21 assigns thechannelization codes of the group A to all data channels of the I and Qaxes and stores in the memory 15. Or the code assigning unit by gainfactor 21 assigns the channelization codes of the group B to all datachannels of the I and Q axes and stores in the memory 15. At STEP4605,the code assigning unit by gain factor 21 assigns the channelizationcodes of the group B to the data channel with the smallest SF among thedata channels of the I axis to which no channelization code is assignedand stores in the memory 15. At STEP4606, the code assigning unit bygain factor 21 judges if there is any data channel of the I axis towhich no channelization code is assigned. If there is a data channel towhich no channelization code is assigned, STEP4607 is implemented. Onthe other hand, if there is no data channel to which no channelizationcode is assigned, STEP4609 is implemented. At STEP4607, it is judged ifwhen the code assigning unit by gain factor 21 assigns thechannelization codes of the group B to the data channels of the I axisto which no channelization code is assigned, the assignment causes toclash with another channel. If it is judged to cause to clash, STEP4608is implemented. If it is judged not to cause to clash, STEP4605 isimplemented. At STEP4608, the remaining code assigning unit 22 assignsthe group A to all data channels of the I axis to which nochannelization code is assigned and stores in the memory 15. AtSTEP4609, the code assigning unit by gain factor 21 assigns thechannelization codes of the group B to the data channel with thesmallest SF among the data channels of the Q axis to which nochannelization code is assigned and stores in the memory 15. AtSTEP4610, the code assigning unit by gain factor 21 judges if there isany data channel of the Q axis to which no channelization code isassigned. If there is a data channel to which no channelization code isassigned, STEP4611 is implemented. If there is no data channel to whichno channelization code is assigned, the operation terminates. AtSTEP4611, the code assigning unit by gain factor 21 judges if theassignment of the channelization codes of the group B to the remainingdata channels of the Q axis cause to clash with another channel. If itis judged to cause to clash, STEP4612 is implemented. If it is judgednot to cause to clash, STEP4609 is implemented. At STEP4612, theremaining code assigning unit 22 assigns the group A to all datachannels of the Q axis to which no channelization code is assigned andstores in the memory 15.

According to the present embodiment, by assigning the channelizationcodes to channels from a channel of which a degree of determining thephase variation is high, it is possible to determine the combination ofthe channelization codes which creates less overshoot by using a moresmall-scale H/W.

INDUSTRIAL APPLICABILITY

By producing a CDMA terminal using the embodiment, it is possible toproduce a terminal of which PAR is small.

Further, adjacent channel leak power due to non-linear distortion can bereduced in an amplifier used for amplifying the power, so that it ispossible to produce a small CDMA terminal with low power consumption ata low cost.

Explanation of Signs

10: CPU, 11: a code combination creating unit, 12: an inter-chip phasevariation calculating unit, 13: a code combination determining unit, 14:a code assignment instructing unit, 15: a memory, 21: a code assigningunit by gain factor, 22: a remaining code assigning unit, 31: a codeassigning unit by data amount, 41: a prohibited code judging unit, 900:a protocol processing unit, 901: a transmitting unit, 902: a modulatingunit, 903: a scrambling code generator, 904: a channelization codegenerator, 905: a controlling unit, 906: a D/A converter, 907: afrequency changing unit, 908: a power amplifying unit, 909: an antenna,910: a low noise amplifying unit, 911: a frequency changing unit, and912: a receiving unit.

1. A communication apparatus comprising: an IQ multiplexing unit formultiplexing a plurality of data channels and a control channel at an Iside and a Q side to generate a complex signal; a transmitting unit formodulating and transmitting the complex signal generated by the IQmultiplexing unit; and a controlling unit for controlling assignment ofchannelization codes for a data channel and a control channel at the Iside and the Q side multiplexed by the IQ multiplexing unit, wherein thecontrolling unit comprises: a code assigning unit by factor for, basedon a size of a factor that is multiplied to the data channel and thecontrol channel by the IQ multiplexing unit, assigning a firstchannelization code to a data channel of which the factor is large; anda remaining code assigning unit for assigning a second channelizationcode being different from the first channelization code to a datachannel to which no channelization code has been assigned by the codeassigning unit by factor.
 2. The communication apparatus of claim 1,wherein the code assigning unit by factor comprises a prohibited codejudging unit for, when a second control channel is added as a controlchannel, judging which of the I side or the Q side of the IQmultiplexing unit the second control channel is added, and, at the Iside or the Q side to which the second control channel is added,prohibiting assignment of a channelization code that has a correlationwith a channelization code to be assigned to the second control channel.3. The communication apparatus of claim 1, wherein: the factor is a gainfactor; and the controlling unit, when a number of data channelsmultiplexed by the IQ multiplexing unit is five, among three datachannels at the I side of the IQ multiplexing unit, assigns C_(4,2) andC_(4,3) respectively as channelization codes to two data channels havinglargest gain factors and assigns either C_(4,1) or C_(4,0) to aremaining one data channel.
 4. The communication apparatus of claim 1,wherein: the factor is a gain factor; and the controlling unit, when anumber of data channels multiplexed by the IQ multiplexing unit is six,among three data channels at the I side of the IQ multiplexing unit,assigns C_(4,2) and C_(4,3) respectively as channelization codes to twodata channels having largest gain factors and assigns C_(4,1) to aremaining one data channel, and among three data channels at the Q sideof the IQ multiplexing unit, assigns C_(4,2) and C_(4,3) respectively aschannelization codes to two data channels having largest gain factorsand assigns either C_(4,1) or C_(4,0) to a remaining one data channel.5. The communication apparatus of claim 1, wherein the controlling unitcontrols assignment of channelization code C_(SF,k) of which a spreadingfactor is SF and a code number is k, assigns a channelization code ofwhich the code number k is 0≦k (SF/2−1) as the first channelizationcode, and assigns a channelization code of which the code number k is(SF/2)≦k≦(SF−1) as the second channelization code.
 6. The communicationapparatus of claim 5, wherein the controlling unit, in case of assigningchannelization codes to a data channel of which the spreading factor SFis 2 and to a data channel of which the spreading factor SF is 4,assigns C_(2,0) to the data channel of which the spreading factor SF is2 as the first channelization code and assigns C_(4,0) or C_(4,1) to thedata channel of which the spreading factor SF is 4 as the secondchannelization code.
 7. The communication apparatus of claim 1, whereinthe controlling unit controls assignment of channelization code C_(SF,k)of which a spreading factor is SF and a code number is k, assigns achannelization code of which the code number k is 0≦k≦(SF/2−1) as thesecond channelization code, and assigns a channelization code of whichthe code number k is (SF/2)≦k≦(SF−1) as the first channelization code.8. The communication apparatus of claim 7, wherein the controlling unit,in case of assigning channelization codes to a data channel of which thespreading factor SF is 2 and to a data channel of which the spreadingfactor is 4, assigns C_(2,1) to the data channel of which the spreadingfactor SF is 2 as the first channelization code and assigns C_(4,0) orC_(4,1) to the data channel of which the spreading factor SF is 4 as thesecond channelization code.
 9. A communication method comprising: IQmultiplexing a plurality of data channels and a control channel at an Iside and a Q side to generate a complex signal; modulating andtransmitting the complex signal generated by the IQ multiplexing; andcontrolling assignment of channelization codes for a data channel by acontrolling unit and a control channel at the I side and the Q sidemultiplexed by the IQ multiplexing, wherein the controlling comprises:based on a size of a factor that is multiplied to the data channel andthe control channel by the IQ multiplexing, assigning a firstchannelization code to a data channel of which the factor is large; andassigning a second channelization code being different from the firstchannelization code to a data channel to which no channelization codehas been assigned by the assigning of the first channelization code.